tests: replace pycodestyle with black

Drop pycodestyle for code style checking in favor of black. Black is
much faster, stable PEP8 compliant code style checker offering also
automatic formatting. It aims to be very stable and produce smallest
diffs. It's used by many small and big projects.

Running checkstyle with black takes a few seconds with a terse output.
Thus, test-checkstyle-diff is no longer necessary.

Expand scope of checkstyle to all python files in the repo, replacing
test-checkstyle with checkstyle-python.

Also, fixstyle-python is now available for automatic style formatting.

Note: python virtualenv has been consolidated in test/Makefile,
test/requirements*.txt which will eventually be moved to a central
location.  This is required to simply the automated generation of
docker executor images in the CI.

Type: improvement
Change-Id: I022a326603485f58585e879ac0f697fceefbc9c8
Signed-off-by: Klement Sekera <klement.sekera@gmail.com>
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>

1 files changed, 641 insertions, 530 deletions

diff --git a/test/test_dhcp.py b/test/test_dhcp.py
index a3b410c0595..a349356119a 100644
--- a/test/test_dhcp.py
+++ b/test/test_dhcp.py
@@ -16,9 +16,19 @@ from scapy.layers.inet import IP, UDP, ICMP
 from scapy.layers.inet6 import IPv6, in6_getnsmac
 from scapy.utils6 import in6_mactoifaceid
 from scapy.layers.dhcp import DHCP, BOOTP, DHCPTypes
-from scapy.layers.dhcp6 import DHCP6, DHCP6_Solicit, DHCP6_RelayForward, \
-    DHCP6_RelayReply, DHCP6_Advertise, DHCP6OptRelayMsg, DHCP6OptIfaceId, \
-    DHCP6OptStatusCode, DHCP6OptVSS, DHCP6OptClientLinkLayerAddr, DHCP6_Request
+from scapy.layers.dhcp6 import (
+    DHCP6,
+    DHCP6_Solicit,
+    DHCP6_RelayForward,
+    DHCP6_RelayReply,
+    DHCP6_Advertise,
+    DHCP6OptRelayMsg,
+    DHCP6OptIfaceId,
+    DHCP6OptStatusCode,
+    DHCP6OptVSS,
+    DHCP6OptClientLinkLayerAddr,
+    DHCP6_Request,
+)
 from socket import AF_INET, AF_INET6, inet_pton, inet_ntop
 from scapy.utils6 import in6_ptop
 from vpp_papi import mac_pton, VppEnum
@@ -35,7 +45,7 @@ DHCP6_SERVER_PORT = 546
 
 @tag_run_solo
 class TestDHCP(VppTestCase):
-    """ DHCP Test Case """
+    """DHCP Test Case"""
 
     @classmethod
     def setUpClass(cls):
@@ -136,8 +146,7 @@ class TestDHCP(VppTestCase):
                     self.assertEqual(six.byte2int(data[2:3]), 0)
                     self.assertEqual(six.byte2int(data[3:4]), 0)
                     self.assertEqual(six.byte2int(data[4:5]), 0)
-                    self.assertEqual(six.byte2int(data[5:6]),
-                                     intf._sw_if_index)
+                    self.assertEqual(six.byte2int(data[5:6]), intf._sw_if_index)
 
                     #
                     # next sub-option is the IP address of the client side
@@ -179,16 +188,15 @@ class TestDHCP(VppTestCase):
                         self.assertEqual(six.byte2int(data[12:13]), 151)
                         self.assertEqual(six.byte2int(data[13:14]), id_len + 1)
                         self.assertEqual(six.byte2int(data[14:15]), 0)
-                        self.assertEqual(data[15:15 + id_len].decode('ascii'),
-                                         vpn_id)
+                        self.assertEqual(data[15 : 15 + id_len].decode("ascii"), vpn_id)
 
                         # VSS control sub-option
-                        self.assertEqual(six.byte2int(data[15 + len(vpn_id):
-                                                           16 + len(vpn_id)]),
-                                         152)
-                        self.assertEqual(six.byte2int(data[16 + len(vpn_id):
-                                                           17 + len(vpn_id)]),
-                                         0)
+                        self.assertEqual(
+                            six.byte2int(data[15 + len(vpn_id) : 16 + len(vpn_id)]), 152
+                        )
+                        self.assertEqual(
+                            six.byte2int(data[16 + len(vpn_id) : 17 + len(vpn_id)]), 0
+                        )
 
                     found = 1
         self.assertTrue(found)
@@ -200,8 +208,7 @@ class TestDHCP(VppTestCase):
         found = False
         for o in dhcp.options:
             if isinstance(o, tuple):
-                if o[0] == "message-type" \
-                   and DHCPTypes[o[1]] == name:
+                if o[0] == "message-type" and DHCPTypes[o[1]] == name:
                     found = True
         self.assertTrue(found)
 
@@ -219,8 +226,9 @@ class TestDHCP(VppTestCase):
         self.assertEqual(udp.sport, DHCP4_SERVER_PORT)
 
         self.verify_dhcp_msg_type(pkt, "offer")
-        data = self.validate_relay_options(pkt, intf, intf.local_ip4,
-                                           vpn_id, fib_id, oui)
+        data = self.validate_relay_options(
+            pkt, intf, intf.local_ip4, vpn_id, fib_id, oui
+        )
 
     def verify_orig_dhcp_pkt(self, pkt, intf, dscp, l2_bc=True):
         ether = pkt[Ether]
@@ -232,7 +240,7 @@ class TestDHCP(VppTestCase):
 
         ip = pkt[IP]
 
-        if (l2_bc):
+        if l2_bc:
             self.assertEqual(ip.dst, "255.255.255.255")
             self.assertEqual(ip.src, "0.0.0.0")
         else:
@@ -244,17 +252,16 @@ class TestDHCP(VppTestCase):
         self.assertEqual(udp.dport, DHCP4_SERVER_PORT)
         self.assertEqual(udp.sport, DHCP4_CLIENT_PORT)
 
-    def verify_orig_dhcp_discover(self, pkt, intf, hostname, client_id=None,
-                                  broadcast=True, dscp=0):
+    def verify_orig_dhcp_discover(
+        self, pkt, intf, hostname, client_id=None, broadcast=True, dscp=0
+    ):
         self.verify_orig_dhcp_pkt(pkt, intf, dscp)
 
         self.verify_dhcp_msg_type(pkt, "discover")
-        self.verify_dhcp_has_option(pkt, "hostname",
-                                    hostname.encode('ascii'))
+        self.verify_dhcp_has_option(pkt, "hostname", hostname.encode("ascii"))
         if client_id:
-            client_id = '\x00' + client_id
-            self.verify_dhcp_has_option(pkt, "client_id",
-                                        client_id.encode('ascii'))
+            client_id = "\x00" + client_id
+            self.verify_dhcp_has_option(pkt, "client_id", client_id.encode("ascii"))
         bootp = pkt[BOOTP]
         self.assertEqual(bootp.ciaddr, "0.0.0.0")
         self.assertEqual(bootp.giaddr, "0.0.0.0")
@@ -263,15 +270,13 @@ class TestDHCP(VppTestCase):
         else:
             self.assertEqual(bootp.flags, 0x0000)
 
-    def verify_orig_dhcp_request(self, pkt, intf, hostname, ip,
-                                 broadcast=True,
-                                 l2_bc=True,
-                                 dscp=0):
+    def verify_orig_dhcp_request(
+        self, pkt, intf, hostname, ip, broadcast=True, l2_bc=True, dscp=0
+    ):
         self.verify_orig_dhcp_pkt(pkt, intf, dscp, l2_bc=l2_bc)
 
         self.verify_dhcp_msg_type(pkt, "request")
-        self.verify_dhcp_has_option(pkt, "hostname",
-                                    hostname.encode('ascii'))
+        self.verify_dhcp_has_option(pkt, "hostname", hostname.encode("ascii"))
         self.verify_dhcp_has_option(pkt, "requested_addr", ip)
         bootp = pkt[BOOTP]
 
@@ -286,10 +291,17 @@ class TestDHCP(VppTestCase):
         else:
             self.assertEqual(bootp.flags, 0x0000)
 
-    def verify_relayed_dhcp_discover(self, pkt, intf, src_intf=None,
-                                     fib_id=0, oui=0,
-                                     vpn_id="",
-                                     dst_mac=None, dst_ip=None):
+    def verify_relayed_dhcp_discover(
+        self,
+        pkt,
+        intf,
+        src_intf=None,
+        fib_id=0,
+        oui=0,
+        vpn_id="",
+        dst_mac=None,
+        dst_ip=None,
+    ):
         if not dst_mac:
             dst_mac = intf.remote_mac
         if not dst_ip:
@@ -312,24 +324,27 @@ class TestDHCP(VppTestCase):
         is_discover = False
         for o in dhcp.options:
             if isinstance(o, tuple):
-                if o[0] == "message-type" \
-                   and DHCPTypes[o[1]] == "discover":
+                if o[0] == "message-type" and DHCPTypes[o[1]] == "discover":
                     is_discover = True
         self.assertTrue(is_discover)
 
-        data = self.validate_relay_options(pkt, src_intf,
-                                           src_intf.local_ip4,
-                                           vpn_id,
-                                           fib_id, oui)
+        data = self.validate_relay_options(
+            pkt, src_intf, src_intf.local_ip4, vpn_id, fib_id, oui
+        )
         return data
 
-    def verify_dhcp6_solicit(self, pkt, intf,
-                             peer_ip, peer_mac,
-                             vpn_id="",
-                             fib_id=0,
-                             oui=0,
-                             dst_mac=None,
-                             dst_ip=None):
+    def verify_dhcp6_solicit(
+        self,
+        pkt,
+        intf,
+        peer_ip,
+        peer_mac,
+        vpn_id="",
+        fib_id=0,
+        oui=0,
+        dst_mac=None,
+        dst_ip=None,
+    ):
         if not dst_mac:
             dst_mac = intf.remote_mac
         if not dst_ip:
@@ -377,8 +392,7 @@ class TestDHCP(VppTestCase):
             vss = pkt[DHCP6OptVSS]
             self.assertEqual(vss.optlen, id_len + 1)
             self.assertEqual(vss.type, 0)
-            self.assertEqual(vss.data[0:id_len].decode('ascii'),
-                             vpn_id)
+            self.assertEqual(vss.data[0:id_len].decode("ascii"), vpn_id)
 
         # the relay message should be an encoded Solicit
         msg = pkt[DHCP6OptRelayMsg]
@@ -402,9 +416,8 @@ class TestDHCP(VppTestCase):
         # not sure why this is not decoding
         # adv = pkt[DHCP6_Advertise]
 
-    def wait_for_no_route(self, address, length,
-                          n_tries=50, s_time=1):
-        while (n_tries):
+    def wait_for_no_route(self, address, length, n_tries=50, s_time=1):
+        while n_tries:
             if not find_route(self, address, length):
                 return True
             n_tries = n_tries - 1
@@ -413,42 +426,45 @@ class TestDHCP(VppTestCase):
         return False
 
     def test_dhcp_proxy(self):
-        """ DHCPv4 Proxy """
+        """DHCPv4 Proxy"""
 
         #
         # Verify no response to DHCP request without DHCP config
         #
-        p_disc_vrf0 = (Ether(dst="ff:ff:ff:ff:ff:ff",
-                             src=self.pg3.remote_mac) /
-                       IP(src="0.0.0.0", dst="255.255.255.255") /
-                       UDP(sport=DHCP4_CLIENT_PORT,
-                           dport=DHCP4_SERVER_PORT) /
-                       BOOTP(op=1) /
-                       DHCP(options=[('message-type', 'discover'), ('end')]))
+        p_disc_vrf0 = (
+            Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg3.remote_mac)
+            / IP(src="0.0.0.0", dst="255.255.255.255")
+            / UDP(sport=DHCP4_CLIENT_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(options=[("message-type", "discover"), ("end")])
+        )
         pkts_disc_vrf0 = [p_disc_vrf0]
-        p_disc_vrf1 = (Ether(dst="ff:ff:ff:ff:ff:ff",
-                             src=self.pg4.remote_mac) /
-                       IP(src="0.0.0.0", dst="255.255.255.255") /
-                       UDP(sport=DHCP4_CLIENT_PORT,
-                           dport=DHCP4_SERVER_PORT) /
-                       BOOTP(op=1) /
-                       DHCP(options=[('message-type', 'discover'), ('end')]))
+        p_disc_vrf1 = (
+            Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg4.remote_mac)
+            / IP(src="0.0.0.0", dst="255.255.255.255")
+            / UDP(sport=DHCP4_CLIENT_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(options=[("message-type", "discover"), ("end")])
+        )
         pkts_disc_vrf1 = [p_disc_vrf1]
-        p_disc_vrf2 = (Ether(dst="ff:ff:ff:ff:ff:ff",
-                             src=self.pg5.remote_mac) /
-                       IP(src="0.0.0.0", dst="255.255.255.255") /
-                       UDP(sport=DHCP4_CLIENT_PORT,
-                           dport=DHCP4_SERVER_PORT) /
-                       BOOTP(op=1) /
-                       DHCP(options=[('message-type', 'discover'), ('end')]))
+        p_disc_vrf2 = (
+            Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg5.remote_mac)
+            / IP(src="0.0.0.0", dst="255.255.255.255")
+            / UDP(sport=DHCP4_CLIENT_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(options=[("message-type", "discover"), ("end")])
+        )
         pkts_disc_vrf2 = [p_disc_vrf2]
 
-        self.send_and_assert_no_replies(self.pg3, pkts_disc_vrf0,
-                                        "DHCP with no configuration")
-        self.send_and_assert_no_replies(self.pg4, pkts_disc_vrf1,
-                                        "DHCP with no configuration")
-        self.send_and_assert_no_replies(self.pg5, pkts_disc_vrf2,
-                                        "DHCP with no configuration")
+        self.send_and_assert_no_replies(
+            self.pg3, pkts_disc_vrf0, "DHCP with no configuration"
+        )
+        self.send_and_assert_no_replies(
+            self.pg4, pkts_disc_vrf1, "DHCP with no configuration"
+        )
+        self.send_and_assert_no_replies(
+            self.pg5, pkts_disc_vrf2, "DHCP with no configuration"
+        )
 
         #
         # Enable DHCP proxy in VRF 0
@@ -463,23 +479,25 @@ class TestDHCP(VppTestCase):
         # Discover packets from the client are dropped because there is no
         # IP address configured on the client facing interface
         #
-        self.send_and_assert_no_replies(self.pg3, pkts_disc_vrf0,
-                                        "Discover DHCP no relay address")
+        self.send_and_assert_no_replies(
+            self.pg3, pkts_disc_vrf0, "Discover DHCP no relay address"
+        )
 
         #
         # Inject a response from the server
         #  dropped, because there is no IP addrees on the
         #  client interfce to fill in the option.
         #
-        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-             IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4) /
-             UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT) /
-             BOOTP(op=1) /
-             DHCP(options=[('message-type', 'offer'), ('end')]))
+        p = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(options=[("message-type", "offer"), ("end")])
+        )
         pkts = [p]
 
-        self.send_and_assert_no_replies(self.pg3, pkts,
-                                        "Offer DHCP no relay address")
+        self.send_and_assert_no_replies(self.pg3, pkts, "Offer DHCP no relay address")
 
         #
         # configure an IP address on the client facing interface
@@ -500,21 +518,26 @@ class TestDHCP(VppTestCase):
         rx = self.pg0.get_capture(1)
         rx = rx[0]
 
-        option_82 = self.verify_relayed_dhcp_discover(rx, self.pg0,
-                                                      src_intf=self.pg3)
+        option_82 = self.verify_relayed_dhcp_discover(rx, self.pg0, src_intf=self.pg3)
 
         #
         # Create an DHCP offer reply from the server with a correctly formatted
         # option 82. i.e. send back what we just captured
         # The offer, sent mcast to the client, still has option 82.
         #
-        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-             IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4) /
-             UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT) /
-             BOOTP(op=1) /
-             DHCP(options=[('message-type', 'offer'),
-                           ('relay_agent_Information', option_82),
-                           ('end')]))
+        p = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("relay_agent_Information", option_82),
+                    ("end"),
+                ]
+            )
+        )
         pkts = [p]
 
         self.pg0.add_stream(pkts)
@@ -533,36 +556,51 @@ class TestDHCP(VppTestCase):
         #    to client
         bad_ip = option_82[0:8] + scapy.compat.chb(33) + option_82[9:]
 
-        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-             IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4) /
-             UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT) /
-             BOOTP(op=1) /
-             DHCP(options=[('message-type', 'offer'),
-                           ('relay_agent_Information', bad_ip),
-                           ('end')]))
+        p = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("relay_agent_Information", bad_ip),
+                    ("end"),
+                ]
+            )
+        )
         pkts = [p]
-        self.send_and_assert_no_replies(self.pg0, pkts,
-                                        "DHCP offer option 82 bad address")
+        self.send_and_assert_no_replies(
+            self.pg0, pkts, "DHCP offer option 82 bad address"
+        )
 
         # 2. Not a sw_if_index VPP knows
         bad_if_index = option_82[0:2] + scapy.compat.chb(33) + option_82[3:]
 
-        p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-             IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4) /
-             UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT) /
-             BOOTP(op=1) /
-             DHCP(options=[('message-type', 'offer'),
-                           ('relay_agent_Information', bad_if_index),
-                           ('end')]))
+        p = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IP(src=self.pg0.remote_ip4, dst=self.pg0.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("relay_agent_Information", bad_if_index),
+                    ("end"),
+                ]
+            )
+        )
         pkts = [p]
-        self.send_and_assert_no_replies(self.pg0, pkts,
-                                        "DHCP offer option 82 bad if index")
+        self.send_and_assert_no_replies(
+            self.pg0, pkts, "DHCP offer option 82 bad if index"
+        )
 
         #
         # Send a DHCP request in VRF 1. should be dropped.
         #
-        self.send_and_assert_no_replies(self.pg4, pkts_disc_vrf1,
-                                        "DHCP with no configuration VRF 1")
+        self.send_and_assert_no_replies(
+            self.pg4, pkts_disc_vrf1, "DHCP with no configuration VRF 1"
+        )
 
         #
         # Delete the DHCP config in VRF 0
@@ -570,10 +608,12 @@ class TestDHCP(VppTestCase):
         #
         Proxy.remove_vpp_config()
 
-        self.send_and_assert_no_replies(self.pg3, pkts_disc_vrf0,
-                                        "DHCP config removed VRF 0")
-        self.send_and_assert_no_replies(self.pg4, pkts_disc_vrf1,
-                                        "DHCP config removed VRF 1")
+        self.send_and_assert_no_replies(
+            self.pg3, pkts_disc_vrf0, "DHCP config removed VRF 0"
+        )
+        self.send_and_assert_no_replies(
+            self.pg4, pkts_disc_vrf1, "DHCP config removed VRF 1"
+        )
 
         #
         # Add DHCP config for VRF 1 & 2
@@ -581,31 +621,27 @@ class TestDHCP(VppTestCase):
         server_addr1 = self.pg1.remote_ip4
         src_addr1 = self.pg1.local_ip4
         Proxy1 = VppDHCPProxy(
-            self,
-            server_addr1,
-            src_addr1,
-            rx_vrf_id=1,
-            server_vrf_id=1)
+            self, server_addr1, src_addr1, rx_vrf_id=1, server_vrf_id=1
+        )
         Proxy1.add_vpp_config()
 
         server_addr2 = self.pg2.remote_ip4
         src_addr2 = self.pg2.local_ip4
         Proxy2 = VppDHCPProxy(
-            self,
-            server_addr2,
-            src_addr2,
-            rx_vrf_id=2,
-            server_vrf_id=2)
+            self, server_addr2, src_addr2, rx_vrf_id=2, server_vrf_id=2
+        )
         Proxy2.add_vpp_config()
 
         #
         # Confim DHCP requests ok in VRF 1 & 2.
         #  - dropped on IP config on client interface
         #
-        self.send_and_assert_no_replies(self.pg4, pkts_disc_vrf1,
-                                        "DHCP config removed VRF 1")
-        self.send_and_assert_no_replies(self.pg5, pkts_disc_vrf2,
-                                        "DHCP config removed VRF 2")
+        self.send_and_assert_no_replies(
+            self.pg4, pkts_disc_vrf1, "DHCP config removed VRF 1"
+        )
+        self.send_and_assert_no_replies(
+            self.pg5, pkts_disc_vrf2, "DHCP config removed VRF 2"
+        )
 
         #
         # configure an IP address on the client facing interface
@@ -630,10 +666,10 @@ class TestDHCP(VppTestCase):
         # Add VSS config
         #  table=1, vss_type=1, vpn_index=1, oui=4
         #  table=2, vss_type=0, vpn_id = "ip4-table-2"
-        self.vapi.dhcp_proxy_set_vss(tbl_id=1, vss_type=1,
-                                     vpn_index=1, oui=4, is_add=1)
-        self.vapi.dhcp_proxy_set_vss(tbl_id=2, vss_type=0,
-                                     vpn_ascii_id="ip4-table-2", is_add=1)
+        self.vapi.dhcp_proxy_set_vss(tbl_id=1, vss_type=1, vpn_index=1, oui=4, is_add=1)
+        self.vapi.dhcp_proxy_set_vss(
+            tbl_id=2, vss_type=0, vpn_ascii_id="ip4-table-2", is_add=1
+        )
 
         self.pg4.add_stream(pkts_disc_vrf1)
         self.pg_enable_capture(self.pg_interfaces)
@@ -641,9 +677,9 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg1.get_capture(1)
         rx = rx[0]
-        self.verify_relayed_dhcp_discover(rx, self.pg1,
-                                          src_intf=self.pg4,
-                                          fib_id=1, oui=4)
+        self.verify_relayed_dhcp_discover(
+            rx, self.pg1, src_intf=self.pg4, fib_id=1, oui=4
+        )
 
         self.pg5.add_stream(pkts_disc_vrf2)
         self.pg_enable_capture(self.pg_interfaces)
@@ -651,9 +687,9 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg2.get_capture(1)
         rx = rx[0]
-        self.verify_relayed_dhcp_discover(rx, self.pg2,
-                                          src_intf=self.pg5,
-                                          vpn_id="ip4-table-2")
+        self.verify_relayed_dhcp_discover(
+            rx, self.pg2, src_intf=self.pg5, vpn_id="ip4-table-2"
+        )
 
         #
         # Add a second DHCP server in VRF 1
@@ -663,20 +699,19 @@ class TestDHCP(VppTestCase):
         server_addr12 = self.pg1.remote_hosts[1].ip4
 
         Proxy12 = VppDHCPProxy(
-            self,
-            server_addr12,
-            src_addr,
-            rx_vrf_id=1,
-            server_vrf_id=1)
+            self, server_addr12, src_addr, rx_vrf_id=1, server_vrf_id=1
+        )
         Proxy12.add_vpp_config()
 
         #
         # We'll need an ARP entry for the server to send it packets
         #
-        arp_entry = VppNeighbor(self,
-                                self.pg1.sw_if_index,
-                                self.pg1.remote_hosts[1].mac,
-                                self.pg1.remote_hosts[1].ip4)
+        arp_entry = VppNeighbor(
+            self,
+            self.pg1.sw_if_index,
+            self.pg1.remote_hosts[1].mac,
+            self.pg1.remote_hosts[1].ip4,
+        )
         arp_entry.add_vpp_config()
 
         #
@@ -691,32 +726,47 @@ class TestDHCP(VppTestCase):
         rx = self.pg1.get_capture(2)
 
         option_82 = self.verify_relayed_dhcp_discover(
-            rx[0], self.pg1,
+            rx[0],
+            self.pg1,
             src_intf=self.pg4,
             dst_mac=self.pg1.remote_hosts[1].mac,
             dst_ip=self.pg1.remote_hosts[1].ip4,
-            fib_id=1, oui=4)
-        self.verify_relayed_dhcp_discover(rx[1], self.pg1,
-                                          src_intf=self.pg4,
-                                          fib_id=1, oui=4)
+            fib_id=1,
+            oui=4,
+        )
+        self.verify_relayed_dhcp_discover(
+            rx[1], self.pg1, src_intf=self.pg4, fib_id=1, oui=4
+        )
 
         #
         # Send both packets back. Client gets both.
         #
-        p1 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
-              IP(src=self.pg1.remote_ip4, dst=self.pg1.local_ip4) /
-              UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT) /
-              BOOTP(op=1) /
-              DHCP(options=[('message-type', 'offer'),
-                            ('relay_agent_Information', option_82),
-                            ('end')]))
-        p2 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
-              IP(src=self.pg1.remote_hosts[1].ip4, dst=self.pg1.local_ip4) /
-              UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT) /
-              BOOTP(op=1) /
-              DHCP(options=[('message-type', 'offer'),
-                            ('relay_agent_Information', option_82),
-                            ('end')]))
+        p1 = (
+            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
+            / IP(src=self.pg1.remote_ip4, dst=self.pg1.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("relay_agent_Information", option_82),
+                    ("end"),
+                ]
+            )
+        )
+        p2 = (
+            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
+            / IP(src=self.pg1.remote_hosts[1].ip4, dst=self.pg1.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("relay_agent_Information", option_82),
+                    ("end"),
+                ]
+            )
+        )
         pkts = [p1, p2]
 
         self.pg1.add_stream(pkts)
@@ -731,27 +781,31 @@ class TestDHCP(VppTestCase):
         #
         # Ensure offers from non-servers are dropeed
         #
-        p2 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
-              IP(src="8.8.8.8", dst=self.pg1.local_ip4) /
-              UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT) /
-              BOOTP(op=1) /
-              DHCP(options=[('message-type', 'offer'),
-                            ('relay_agent_Information', option_82),
-                            ('end')]))
-        self.send_and_assert_no_replies(self.pg1, p2,
-                                        "DHCP offer from non-server")
+        p2 = (
+            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
+            / IP(src="8.8.8.8", dst=self.pg1.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("relay_agent_Information", option_82),
+                    ("end"),
+                ]
+            )
+        )
+        self.send_and_assert_no_replies(self.pg1, p2, "DHCP offer from non-server")
 
         #
         # Ensure only the discover is sent to multiple servers
         #
-        p_req_vrf1 = (Ether(dst="ff:ff:ff:ff:ff:ff",
-                            src=self.pg4.remote_mac) /
-                      IP(src="0.0.0.0", dst="255.255.255.255") /
-                      UDP(sport=DHCP4_CLIENT_PORT,
-                          dport=DHCP4_SERVER_PORT) /
-                      BOOTP(op=1) /
-                      DHCP(options=[('message-type', 'request'),
-                                    ('end')]))
+        p_req_vrf1 = (
+            Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg4.remote_mac)
+            / IP(src="0.0.0.0", dst="255.255.255.255")
+            / UDP(sport=DHCP4_CLIENT_PORT, dport=DHCP4_SERVER_PORT)
+            / BOOTP(op=1)
+            / DHCP(options=[("message-type", "request"), ("end")])
+        )
 
         self.pg4.add_stream(p_req_vrf1)
         self.pg_enable_capture(self.pg_interfaces)
@@ -773,9 +827,9 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg1.get_capture(1)
         rx = rx[0]
-        self.verify_relayed_dhcp_discover(rx, self.pg1,
-                                          src_intf=self.pg4,
-                                          fib_id=1, oui=4)
+        self.verify_relayed_dhcp_discover(
+            rx, self.pg1, src_intf=self.pg4, fib_id=1, oui=4
+        )
 
         #
         # Remove the VSS config
@@ -798,19 +852,16 @@ class TestDHCP(VppTestCase):
         Proxy1.remove_vpp_config()
         Proxy2.remove_vpp_config()
 
-        self.send_and_assert_no_replies(self.pg3, pkts_disc_vrf0,
-                                        "DHCP cleanup VRF 0")
-        self.send_and_assert_no_replies(self.pg4, pkts_disc_vrf1,
-                                        "DHCP cleanup VRF 1")
-        self.send_and_assert_no_replies(self.pg5, pkts_disc_vrf2,
-                                        "DHCP cleanup VRF 2")
+        self.send_and_assert_no_replies(self.pg3, pkts_disc_vrf0, "DHCP cleanup VRF 0")
+        self.send_and_assert_no_replies(self.pg4, pkts_disc_vrf1, "DHCP cleanup VRF 1")
+        self.send_and_assert_no_replies(self.pg5, pkts_disc_vrf2, "DHCP cleanup VRF 2")
 
         self.pg3.unconfig_ip4()
         self.pg4.unconfig_ip4()
         self.pg5.unconfig_ip4()
 
     def test_dhcp6_proxy(self):
-        """ DHCPv6 Proxy"""
+        """DHCPv6 Proxy"""
         #
         # Verify no response to DHCP request without DHCP config
         #
@@ -826,31 +877,34 @@ class TestDHCP(VppTestCase):
         src_addr_vrf2 = self.pg2.local_ip6
 
         dmac = in6_getnsmac(inet_pton(socket.AF_INET6, dhcp_solicit_dst))
-        p_solicit_vrf0 = (Ether(dst=dmac, src=self.pg3.remote_mac) /
-                          IPv6(src=dhcp_solicit_src_vrf0,
-                               dst=dhcp_solicit_dst) /
-                          UDP(sport=DHCP6_SERVER_PORT,
-                              dport=DHCP6_CLIENT_PORT) /
-                          DHCP6_Solicit())
-        p_solicit_vrf1 = (Ether(dst=dmac, src=self.pg4.remote_mac) /
-                          IPv6(src=dhcp_solicit_src_vrf1,
-                               dst=dhcp_solicit_dst) /
-                          UDP(sport=DHCP6_SERVER_PORT,
-                              dport=DHCP6_CLIENT_PORT) /
-                          DHCP6_Solicit())
-        p_solicit_vrf2 = (Ether(dst=dmac, src=self.pg5.remote_mac) /
-                          IPv6(src=dhcp_solicit_src_vrf2,
-                               dst=dhcp_solicit_dst) /
-                          UDP(sport=DHCP6_SERVER_PORT,
-                              dport=DHCP6_CLIENT_PORT) /
-                          DHCP6_Solicit())
-
-        self.send_and_assert_no_replies(self.pg3, p_solicit_vrf0,
-                                        "DHCP with no configuration")
-        self.send_and_assert_no_replies(self.pg4, p_solicit_vrf1,
-                                        "DHCP with no configuration")
-        self.send_and_assert_no_replies(self.pg5, p_solicit_vrf2,
-                                        "DHCP with no configuration")
+        p_solicit_vrf0 = (
+            Ether(dst=dmac, src=self.pg3.remote_mac)
+            / IPv6(src=dhcp_solicit_src_vrf0, dst=dhcp_solicit_dst)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_CLIENT_PORT)
+            / DHCP6_Solicit()
+        )
+        p_solicit_vrf1 = (
+            Ether(dst=dmac, src=self.pg4.remote_mac)
+            / IPv6(src=dhcp_solicit_src_vrf1, dst=dhcp_solicit_dst)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_CLIENT_PORT)
+            / DHCP6_Solicit()
+        )
+        p_solicit_vrf2 = (
+            Ether(dst=dmac, src=self.pg5.remote_mac)
+            / IPv6(src=dhcp_solicit_src_vrf2, dst=dhcp_solicit_dst)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_CLIENT_PORT)
+            / DHCP6_Solicit()
+        )
+
+        self.send_and_assert_no_replies(
+            self.pg3, p_solicit_vrf0, "DHCP with no configuration"
+        )
+        self.send_and_assert_no_replies(
+            self.pg4, p_solicit_vrf1, "DHCP with no configuration"
+        )
+        self.send_and_assert_no_replies(
+            self.pg5, p_solicit_vrf2, "DHCP with no configuration"
+        )
 
         #
         # DHCPv6 config in VRF 0.
@@ -858,17 +912,16 @@ class TestDHCP(VppTestCase):
         # IPv6 config
         #
         Proxy = VppDHCPProxy(
-            self,
-            server_addr_vrf0,
-            src_addr_vrf0,
-            rx_vrf_id=0,
-            server_vrf_id=0)
+            self, server_addr_vrf0, src_addr_vrf0, rx_vrf_id=0, server_vrf_id=0
+        )
         Proxy.add_vpp_config()
 
-        self.send_and_assert_no_replies(self.pg3, p_solicit_vrf0,
-                                        "DHCP with no configuration")
-        self.send_and_assert_no_replies(self.pg4, p_solicit_vrf1,
-                                        "DHCP with no configuration")
+        self.send_and_assert_no_replies(
+            self.pg3, p_solicit_vrf0, "DHCP with no configuration"
+        )
+        self.send_and_assert_no_replies(
+            self.pg4, p_solicit_vrf1, "DHCP with no configuration"
+        )
 
         #
         # configure an IP address on the client facing interface
@@ -884,62 +937,70 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg0.get_capture(1)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg0,
-                                  dhcp_solicit_src_vrf0,
-                                  self.pg3.remote_mac)
+        self.verify_dhcp6_solicit(
+            rx[0], self.pg0, dhcp_solicit_src_vrf0, self.pg3.remote_mac
+        )
 
         #
         # Exception cases for rejected relay responses
         #
 
         # 1 - not a relay reply
-        p_adv_vrf0 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-                      IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6) /
-                      UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-                      DHCP6_Advertise())
-        self.send_and_assert_no_replies(self.pg3, p_adv_vrf0,
-                                        "DHCP6 not a relay reply")
+        p_adv_vrf0 = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_Advertise()
+        )
+        self.send_and_assert_no_replies(self.pg3, p_adv_vrf0, "DHCP6 not a relay reply")
 
         # 2 - no relay message option
-        p_adv_vrf0 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-                      IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6) /
-                      UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-                      DHCP6_RelayReply() /
-                      DHCP6_Advertise())
-        self.send_and_assert_no_replies(self.pg3, p_adv_vrf0,
-                                        "DHCP not a relay message")
+        p_adv_vrf0 = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply()
+            / DHCP6_Advertise()
+        )
+        self.send_and_assert_no_replies(
+            self.pg3, p_adv_vrf0, "DHCP not a relay message"
+        )
 
         # 3 - no circuit ID
-        p_adv_vrf0 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-                      IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6) /
-                      UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-                      DHCP6_RelayReply() /
-                      DHCP6OptRelayMsg(optlen=0) /
-                      DHCP6_Advertise())
-        self.send_and_assert_no_replies(self.pg3, p_adv_vrf0,
-                                        "DHCP6 no circuit ID")
+        p_adv_vrf0 = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply()
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise()
+        )
+        self.send_and_assert_no_replies(self.pg3, p_adv_vrf0, "DHCP6 no circuit ID")
         # 4 - wrong circuit ID
-        p_adv_vrf0 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-                      IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6) /
-                      UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-                      DHCP6_RelayReply() /
-                      DHCP6OptIfaceId(optlen=4, ifaceid='\x00\x00\x00\x05') /
-                      DHCP6OptRelayMsg(optlen=0) /
-                      DHCP6_Advertise())
-        self.send_and_assert_no_replies(self.pg3, p_adv_vrf0,
-                                        "DHCP6 wrong circuit ID")
+        p_adv_vrf0 = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply()
+            / DHCP6OptIfaceId(optlen=4, ifaceid="\x00\x00\x00\x05")
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise()
+        )
+        self.send_and_assert_no_replies(self.pg3, p_adv_vrf0, "DHCP6 wrong circuit ID")
 
         #
         # Send the relay response (the advertisement)
         #   - no peer address
-        p_adv_vrf0 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-                      IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6) /
-                      UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-                      DHCP6_RelayReply() /
-                      DHCP6OptIfaceId(optlen=4, ifaceid='\x00\x00\x00\x04') /
-                      DHCP6OptRelayMsg(optlen=0) /
-                      DHCP6_Advertise(trid=1) /
-                      DHCP6OptStatusCode(statuscode=0))
+        p_adv_vrf0 = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply()
+            / DHCP6OptIfaceId(optlen=4, ifaceid="\x00\x00\x00\x04")
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise(trid=1)
+            / DHCP6OptStatusCode(statuscode=0)
+        )
         pkts_adv_vrf0 = [p_adv_vrf0]
 
         self.pg0.add_stream(pkts_adv_vrf0)
@@ -953,14 +1014,16 @@ class TestDHCP(VppTestCase):
         #
         # Send the relay response (the advertisement)
         #   - with peer address
-        p_adv_vrf0 = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
-                      IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6) /
-                      UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-                      DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf0) /
-                      DHCP6OptIfaceId(optlen=4, ifaceid='\x00\x00\x00\x04') /
-                      DHCP6OptRelayMsg(optlen=0) /
-                      DHCP6_Advertise(trid=1) /
-                      DHCP6OptStatusCode(statuscode=0))
+        p_adv_vrf0 = (
+            Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac)
+            / IPv6(dst=self.pg0.local_ip6, src=self.pg0.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf0)
+            / DHCP6OptIfaceId(optlen=4, ifaceid="\x00\x00\x00\x04")
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise(trid=1)
+            / DHCP6OptStatusCode(statuscode=0)
+        )
         pkts_adv_vrf0 = [p_adv_vrf0]
 
         self.pg0.add_stream(pkts_adv_vrf0)
@@ -975,20 +1038,14 @@ class TestDHCP(VppTestCase):
         # Add all the config for VRF 1 & 2
         #
         Proxy1 = VppDHCPProxy(
-            self,
-            server_addr_vrf1,
-            src_addr_vrf1,
-            rx_vrf_id=1,
-            server_vrf_id=1)
+            self, server_addr_vrf1, src_addr_vrf1, rx_vrf_id=1, server_vrf_id=1
+        )
         Proxy1.add_vpp_config()
         self.pg4.config_ip6()
 
         Proxy2 = VppDHCPProxy(
-            self,
-            server_addr_vrf2,
-            src_addr_vrf2,
-            rx_vrf_id=2,
-            server_vrf_id=2)
+            self, server_addr_vrf2, src_addr_vrf2, rx_vrf_id=2, server_vrf_id=2
+        )
         Proxy2.add_vpp_config()
         self.pg5.config_ip6()
 
@@ -1001,9 +1058,9 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg1.get_capture(1)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg1,
-                                  dhcp_solicit_src_vrf1,
-                                  self.pg4.remote_mac)
+        self.verify_dhcp6_solicit(
+            rx[0], self.pg1, dhcp_solicit_src_vrf1, self.pg4.remote_mac
+        )
 
         #
         # VRF 2 solicit
@@ -1014,21 +1071,23 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg2.get_capture(1)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg2,
-                                  dhcp_solicit_src_vrf2,
-                                  self.pg5.remote_mac)
+        self.verify_dhcp6_solicit(
+            rx[0], self.pg2, dhcp_solicit_src_vrf2, self.pg5.remote_mac
+        )
 
         #
         # VRF 1 Advert
         #
-        p_adv_vrf1 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
-                      IPv6(dst=self.pg1.local_ip6, src=self.pg1.remote_ip6) /
-                      UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-                      DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1) /
-                      DHCP6OptIfaceId(optlen=4, ifaceid='\x00\x00\x00\x05') /
-                      DHCP6OptRelayMsg(optlen=0) /
-                      DHCP6_Advertise(trid=1) /
-                      DHCP6OptStatusCode(statuscode=0))
+        p_adv_vrf1 = (
+            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
+            / IPv6(dst=self.pg1.local_ip6, src=self.pg1.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1)
+            / DHCP6OptIfaceId(optlen=4, ifaceid="\x00\x00\x00\x05")
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise(trid=1)
+            / DHCP6OptStatusCode(statuscode=0)
+        )
         pkts_adv_vrf1 = [p_adv_vrf1]
 
         self.pg1.add_stream(pkts_adv_vrf1)
@@ -1043,13 +1102,11 @@ class TestDHCP(VppTestCase):
         # Add VSS config
         #
         self.vapi.dhcp_proxy_set_vss(
-            tbl_id=1, vss_type=1, oui=4, vpn_index=1, is_ipv6=1, is_add=1)
+            tbl_id=1, vss_type=1, oui=4, vpn_index=1, is_ipv6=1, is_add=1
+        )
         self.vapi.dhcp_proxy_set_vss(
-            tbl_id=2,
-            vss_type=0,
-            vpn_ascii_id="IPv6-table-2",
-            is_ipv6=1,
-            is_add=1)
+            tbl_id=2, vss_type=0, vpn_ascii_id="IPv6-table-2", is_ipv6=1, is_add=1
+        )
 
         self.pg4.add_stream(p_solicit_vrf1)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1057,11 +1114,9 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg1.get_capture(1)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg1,
-                                  dhcp_solicit_src_vrf1,
-                                  self.pg4.remote_mac,
-                                  fib_id=1,
-                                  oui=4)
+        self.verify_dhcp6_solicit(
+            rx[0], self.pg1, dhcp_solicit_src_vrf1, self.pg4.remote_mac, fib_id=1, oui=4
+        )
 
         self.pg5.add_stream(p_solicit_vrf2)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1069,10 +1124,13 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg2.get_capture(1)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg2,
-                                  dhcp_solicit_src_vrf2,
-                                  self.pg5.remote_mac,
-                                  vpn_id="IPv6-table-2")
+        self.verify_dhcp6_solicit(
+            rx[0],
+            self.pg2,
+            dhcp_solicit_src_vrf2,
+            self.pg5.remote_mac,
+            vpn_id="IPv6-table-2",
+        )
 
         #
         # Remove the VSS config
@@ -1086,9 +1144,9 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg1.get_capture(1)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg1,
-                                  dhcp_solicit_src_vrf1,
-                                  self.pg4.remote_mac)
+        self.verify_dhcp6_solicit(
+            rx[0], self.pg1, dhcp_solicit_src_vrf1, self.pg4.remote_mac
+        )
 
         #
         # Add a second DHCP server in VRF 1
@@ -1098,20 +1156,19 @@ class TestDHCP(VppTestCase):
         server_addr12 = self.pg1.remote_hosts[1].ip6
 
         Proxy12 = VppDHCPProxy(
-            self,
-            server_addr12,
-            src_addr_vrf1,
-            rx_vrf_id=1,
-            server_vrf_id=1)
+            self, server_addr12, src_addr_vrf1, rx_vrf_id=1, server_vrf_id=1
+        )
         Proxy12.add_vpp_config()
 
         #
         # We'll need an ND entry for the server to send it packets
         #
-        nd_entry = VppNeighbor(self,
-                               self.pg1.sw_if_index,
-                               self.pg1.remote_hosts[1].mac,
-                               self.pg1.remote_hosts[1].ip6)
+        nd_entry = VppNeighbor(
+            self,
+            self.pg1.sw_if_index,
+            self.pg1.remote_hosts[1].mac,
+            self.pg1.remote_hosts[1].ip6,
+        )
         nd_entry.add_vpp_config()
 
         #
@@ -1125,34 +1182,41 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg1.get_capture(2)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg1,
-                                  dhcp_solicit_src_vrf1,
-                                  self.pg4.remote_mac)
-        self.verify_dhcp6_solicit(rx[1], self.pg1,
-                                  dhcp_solicit_src_vrf1,
-                                  self.pg4.remote_mac,
-                                  dst_mac=self.pg1.remote_hosts[1].mac,
-                                  dst_ip=self.pg1.remote_hosts[1].ip6)
+        self.verify_dhcp6_solicit(
+            rx[0], self.pg1, dhcp_solicit_src_vrf1, self.pg4.remote_mac
+        )
+        self.verify_dhcp6_solicit(
+            rx[1],
+            self.pg1,
+            dhcp_solicit_src_vrf1,
+            self.pg4.remote_mac,
+            dst_mac=self.pg1.remote_hosts[1].mac,
+            dst_ip=self.pg1.remote_hosts[1].ip6,
+        )
 
         #
         # Send both packets back. Client gets both.
         #
-        p1 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
-              IPv6(dst=self.pg1.local_ip6, src=self.pg1.remote_ip6) /
-              UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-              DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1) /
-              DHCP6OptIfaceId(optlen=4, ifaceid='\x00\x00\x00\x05') /
-              DHCP6OptRelayMsg(optlen=0) /
-              DHCP6_Advertise(trid=1) /
-              DHCP6OptStatusCode(statuscode=0))
-        p2 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_hosts[1].mac) /
-              IPv6(dst=self.pg1.local_ip6, src=self.pg1._remote_hosts[1].ip6) /
-              UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-              DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1) /
-              DHCP6OptIfaceId(optlen=4, ifaceid='\x00\x00\x00\x05') /
-              DHCP6OptRelayMsg(optlen=0) /
-              DHCP6_Advertise(trid=1) /
-              DHCP6OptStatusCode(statuscode=0))
+        p1 = (
+            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac)
+            / IPv6(dst=self.pg1.local_ip6, src=self.pg1.remote_ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1)
+            / DHCP6OptIfaceId(optlen=4, ifaceid="\x00\x00\x00\x05")
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise(trid=1)
+            / DHCP6OptStatusCode(statuscode=0)
+        )
+        p2 = (
+            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_hosts[1].mac)
+            / IPv6(dst=self.pg1.local_ip6, src=self.pg1._remote_hosts[1].ip6)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1)
+            / DHCP6OptIfaceId(optlen=4, ifaceid="\x00\x00\x00\x05")
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise(trid=1)
+            / DHCP6OptStatusCode(statuscode=0)
+        )
 
         pkts = [p1, p2]
 
@@ -1168,12 +1232,12 @@ class TestDHCP(VppTestCase):
         #
         # Ensure only solicit messages are duplicated
         #
-        p_request_vrf1 = (Ether(dst=dmac, src=self.pg4.remote_mac) /
-                          IPv6(src=dhcp_solicit_src_vrf1,
-                               dst=dhcp_solicit_dst) /
-                          UDP(sport=DHCP6_SERVER_PORT,
-                              dport=DHCP6_CLIENT_PORT) /
-                          DHCP6_Request())
+        p_request_vrf1 = (
+            Ether(dst=dmac, src=self.pg4.remote_mac)
+            / IPv6(src=dhcp_solicit_src_vrf1, dst=dhcp_solicit_dst)
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_CLIENT_PORT)
+            / DHCP6_Request()
+        )
 
         self.pg4.add_stream(p_request_vrf1)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1185,16 +1249,17 @@ class TestDHCP(VppTestCase):
         # Test we drop DHCP packets from addresses that are not configured as
         # DHCP servers
         #
-        p2 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_hosts[1].mac) /
-              IPv6(dst=self.pg1.local_ip6, src="3001::1") /
-              UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT) /
-              DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1) /
-              DHCP6OptIfaceId(optlen=4, ifaceid='\x00\x00\x00\x05') /
-              DHCP6OptRelayMsg(optlen=0) /
-              DHCP6_Advertise(trid=1) /
-              DHCP6OptStatusCode(statuscode=0))
-        self.send_and_assert_no_replies(self.pg1, p2,
-                                        "DHCP6 not from server")
+        p2 = (
+            Ether(dst=self.pg1.local_mac, src=self.pg1.remote_hosts[1].mac)
+            / IPv6(dst=self.pg1.local_ip6, src="3001::1")
+            / UDP(sport=DHCP6_SERVER_PORT, dport=DHCP6_SERVER_PORT)
+            / DHCP6_RelayReply(peeraddr=dhcp_solicit_src_vrf1)
+            / DHCP6OptIfaceId(optlen=4, ifaceid="\x00\x00\x00\x05")
+            / DHCP6OptRelayMsg(optlen=0)
+            / DHCP6_Advertise(trid=1)
+            / DHCP6OptStatusCode(statuscode=0)
+        )
+        self.send_and_assert_no_replies(self.pg1, p2, "DHCP6 not from server")
 
         #
         # Remove the second DHCP server
@@ -1210,9 +1275,9 @@ class TestDHCP(VppTestCase):
 
         rx = self.pg1.get_capture(1)
 
-        self.verify_dhcp6_solicit(rx[0], self.pg1,
-                                  dhcp_solicit_src_vrf1,
-                                  self.pg4.remote_mac)
+        self.verify_dhcp6_solicit(
+            rx[0], self.pg1, dhcp_solicit_src_vrf1, self.pg4.remote_mac
+        )
 
         #
         # Cleanup
@@ -1226,10 +1291,10 @@ class TestDHCP(VppTestCase):
         self.pg5.unconfig_ip6()
 
     def test_dhcp_client(self):
-        """ DHCP Client"""
+        """DHCP Client"""
 
         vdscp = VppEnum.vl_api_ip_dscp_t
-        hostname = 'universal-dp'
+        hostname = "universal-dp"
 
         self.pg_enable_capture(self.pg_interfaces)
 
@@ -1247,38 +1312,50 @@ class TestDHCP(VppTestCase):
         #
         # Send back on offer, expect the request
         #
-        p_offer = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                   IP(src=self.pg3.remote_ip4, dst="255.255.255.255") /
-                   UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                   BOOTP(op=1,
-                         yiaddr=self.pg3.local_ip4,
-                         chaddr=mac_pton(self.pg3.local_mac)) /
-                   DHCP(options=[('message-type', 'offer'),
-                                 ('server_id', self.pg3.remote_ip4),
-                                 'end']))
+        p_offer = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst="255.255.255.255")
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1, yiaddr=self.pg3.local_ip4, chaddr=mac_pton(self.pg3.local_mac)
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("server_id", self.pg3.remote_ip4),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_offer)
         self.pg_enable_capture(self.pg_interfaces)
         self.pg_start()
 
         rx = self.pg3.get_capture(1)
-        self.verify_orig_dhcp_request(rx[0], self.pg3, hostname,
-                                      self.pg3.local_ip4)
+        self.verify_orig_dhcp_request(rx[0], self.pg3, hostname, self.pg3.local_ip4)
 
         #
         # Send an acknowledgment
         #
-        p_ack = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                 IP(src=self.pg3.remote_ip4, dst="255.255.255.255") /
-                 UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                 BOOTP(op=1, yiaddr=self.pg3.local_ip4,
-                       chaddr=mac_pton(self.pg3.local_mac)) /
-                 DHCP(options=[('message-type', 'ack'),
-                               ('subnet_mask', "255.255.255.0"),
-                               ('router', self.pg3.remote_ip4),
-                               ('server_id', self.pg3.remote_ip4),
-                               ('lease_time', 43200),
-                               'end']))
+        p_ack = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst="255.255.255.255")
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1, yiaddr=self.pg3.local_ip4, chaddr=mac_pton(self.pg3.local_mac)
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "ack"),
+                    ("subnet_mask", "255.255.255.0"),
+                    ("router", self.pg3.remote_ip4),
+                    ("server_id", self.pg3.remote_ip4),
+                    ("lease_time", 43200),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_ack)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1317,16 +1394,19 @@ class TestDHCP(VppTestCase):
         self.pg3.admin_down()
         self.sleep(1)
         self.pg3.admin_up()
-        Client.set_client(self.pg3.sw_if_index, hostname,
-                          id=self.pg3.local_mac,
-                          dscp=vdscp.IP_API_DSCP_EF)
+        Client.set_client(
+            self.pg3.sw_if_index,
+            hostname,
+            id=self.pg3.local_mac,
+            dscp=vdscp.IP_API_DSCP_EF,
+        )
         Client.add_vpp_config()
 
         rx = self.pg3.get_capture(1)
 
-        self.verify_orig_dhcp_discover(rx[0], self.pg3, hostname,
-                                       self.pg3.local_mac,
-                                       dscp=vdscp.IP_API_DSCP_EF)
+        self.verify_orig_dhcp_discover(
+            rx[0], self.pg3, hostname, self.pg3.local_mac, dscp=vdscp.IP_API_DSCP_EF
+        )
 
         # TODO: VPP DHCP client should not accept DHCP OFFER message with
         # the XID (Transaction ID) not matching the XID of the most recent
@@ -1338,24 +1418,31 @@ class TestDHCP(VppTestCase):
         self.pg_start()
 
         rx = self.pg3.get_capture(1)
-        self.verify_orig_dhcp_request(rx[0], self.pg3, hostname,
-                                      self.pg3.local_ip4,
-                                      dscp=vdscp.IP_API_DSCP_EF)
+        self.verify_orig_dhcp_request(
+            rx[0], self.pg3, hostname, self.pg3.local_ip4, dscp=vdscp.IP_API_DSCP_EF
+        )
 
         #
         # unicast the ack to the offered address
         #
-        p_ack = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                 IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4) /
-                 UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                 BOOTP(op=1, yiaddr=self.pg3.local_ip4,
-                       chaddr=mac_pton(self.pg3.local_mac)) /
-                 DHCP(options=[('message-type', 'ack'),
-                               ('subnet_mask', "255.255.255.0"),
-                               ('router', self.pg3.remote_ip4),
-                               ('server_id', self.pg3.remote_ip4),
-                               ('lease_time', 43200),
-                               'end']))
+        p_ack = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1, yiaddr=self.pg3.local_ip4, chaddr=mac_pton(self.pg3.local_mac)
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "ack"),
+                    ("subnet_mask", "255.255.255.0"),
+                    ("router", self.pg3.remote_ip4),
+                    ("server_id", self.pg3.remote_ip4),
+                    ("lease_time", 43200),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_ack)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1391,55 +1478,65 @@ class TestDHCP(VppTestCase):
         #
         # Configure DHCP client on PG3 and capture the discover sent
         #
-        Client.set_client(
-            self.pg3.sw_if_index,
-            hostname,
-            set_broadcast_flag=False)
+        Client.set_client(self.pg3.sw_if_index, hostname, set_broadcast_flag=False)
         Client.add_vpp_config()
 
         rx = self.pg3.get_capture(1)
 
-        self.verify_orig_dhcp_discover(rx[0], self.pg3, hostname,
-                                       broadcast=False)
+        self.verify_orig_dhcp_discover(rx[0], self.pg3, hostname, broadcast=False)
 
         #
         # Send back on offer, unicasted to the offered address.
         # Expect the request.
         #
-        p_offer = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                   IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4) /
-                   UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                   BOOTP(op=1, yiaddr=self.pg3.local_ip4,
-                         chaddr=mac_pton(self.pg3.local_mac)) /
-                   DHCP(options=[('message-type', 'offer'),
-                                 ('server_id', self.pg3.remote_ip4),
-                                 'end']))
+        p_offer = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1, yiaddr=self.pg3.local_ip4, chaddr=mac_pton(self.pg3.local_mac)
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("server_id", self.pg3.remote_ip4),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_offer)
         self.pg_enable_capture(self.pg_interfaces)
         self.pg_start()
 
         rx = self.pg3.get_capture(1)
-        self.verify_orig_dhcp_request(rx[0], self.pg3, hostname,
-                                      self.pg3.local_ip4,
-                                      broadcast=False)
+        self.verify_orig_dhcp_request(
+            rx[0], self.pg3, hostname, self.pg3.local_ip4, broadcast=False
+        )
 
         #
         # Send an acknowledgment, the lease renewal time is 2 seconds
         # so we should expect the renew straight after
         #
-        p_ack = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                 IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4) /
-                 UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                 BOOTP(op=1, yiaddr=self.pg3.local_ip4,
-                       chaddr=mac_pton(self.pg3.local_mac)) /
-                 DHCP(options=[('message-type', 'ack'),
-                               ('subnet_mask', "255.255.255.0"),
-                               ('router', self.pg3.remote_ip4),
-                               ('server_id', self.pg3.remote_ip4),
-                               ('lease_time', 43200),
-                               ('renewal_time', 2),
-                               'end']))
+        p_ack = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1, yiaddr=self.pg3.local_ip4, chaddr=mac_pton(self.pg3.local_mac)
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "ack"),
+                    ("subnet_mask", "255.255.255.0"),
+                    ("router", self.pg3.remote_ip4),
+                    ("server_id", self.pg3.remote_ip4),
+                    ("lease_time", 43200),
+                    ("renewal_time", 2),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_ack)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1465,19 +1562,15 @@ class TestDHCP(VppTestCase):
         #
         clients = self.vapi.dhcp_client_dump()
 
-        self.assertEqual(clients[0].client.sw_if_index,
-                         self.pg3.sw_if_index)
-        self.assertEqual(clients[0].lease.sw_if_index,
-                         self.pg3.sw_if_index)
+        self.assertEqual(clients[0].client.sw_if_index, self.pg3.sw_if_index)
+        self.assertEqual(clients[0].lease.sw_if_index, self.pg3.sw_if_index)
         self.assertEqual(clients[0].client.hostname, hostname)
         self.assertEqual(clients[0].lease.hostname, hostname)
         # 0 = DISCOVER, 1 = REQUEST, 2 = BOUND
         self.assertEqual(clients[0].lease.state, 2)
         self.assertEqual(clients[0].lease.mask_width, 24)
-        self.assertEqual(str(clients[0].lease.router_address),
-                         self.pg3.remote_ip4)
-        self.assertEqual(str(clients[0].lease.host_address),
-                         self.pg3.local_ip4)
+        self.assertEqual(str(clients[0].lease.router_address), self.pg3.remote_ip4)
+        self.assertEqual(str(clients[0].lease.host_address), self.pg3.local_ip4)
 
         #
         # wait for the unicasted renewal
@@ -1490,37 +1583,46 @@ class TestDHCP(VppTestCase):
         self.assertEqual(rx[0][ARP].pdst, self.pg3.remote_ip4)
 
         # respond to the arp
-        p_arp = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                 ARP(op="is-at",
-                     hwdst=self.pg3.local_mac,
-                     hwsrc=self.pg3.remote_mac,
-                     pdst=self.pg3.local_ip4,
-                     psrc=self.pg3.remote_ip4))
+        p_arp = Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) / ARP(
+            op="is-at",
+            hwdst=self.pg3.local_mac,
+            hwsrc=self.pg3.remote_mac,
+            pdst=self.pg3.local_ip4,
+            psrc=self.pg3.remote_ip4,
+        )
         self.pg3.add_stream(p_arp)
         self.pg_enable_capture(self.pg_interfaces)
         self.pg_start()
 
         # the next packet is the unicasted renewal
         rx = self.pg3.get_capture(1, timeout=10)
-        self.verify_orig_dhcp_request(rx[0], self.pg3, hostname,
-                                      self.pg3.local_ip4,
-                                      l2_bc=False,
-                                      broadcast=False)
+        self.verify_orig_dhcp_request(
+            rx[0], self.pg3, hostname, self.pg3.local_ip4, l2_bc=False, broadcast=False
+        )
 
         # send an ACK with different data from the original offer *
         self.pg3.generate_remote_hosts(4)
-        p_ack = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                 IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4) /
-                 UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                 BOOTP(op=1, yiaddr=self.pg3.remote_hosts[3].ip4,
-                       chaddr=mac_pton(self.pg3.local_mac)) /
-                 DHCP(options=[('message-type', 'ack'),
-                               ('subnet_mask', "255.255.255.0"),
-                               ('router', self.pg3.remote_hosts[1].ip4),
-                               ('server_id', self.pg3.remote_hosts[2].ip4),
-                               ('lease_time', 43200),
-                               ('renewal_time', 2),
-                               'end']))
+        p_ack = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst=self.pg3.local_ip4)
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1,
+                yiaddr=self.pg3.remote_hosts[3].ip4,
+                chaddr=mac_pton(self.pg3.local_mac),
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "ack"),
+                    ("subnet_mask", "255.255.255.0"),
+                    ("router", self.pg3.remote_hosts[1].ip4),
+                    ("server_id", self.pg3.remote_hosts[2].ip4),
+                    ("lease_time", 43200),
+                    ("renewal_time", 2),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_ack)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1531,19 +1633,19 @@ class TestDHCP(VppTestCase):
         #
         clients = self.vapi.dhcp_client_dump()
 
-        self.assertEqual(clients[0].client.sw_if_index,
-                         self.pg3.sw_if_index)
-        self.assertEqual(clients[0].lease.sw_if_index,
-                         self.pg3.sw_if_index)
+        self.assertEqual(clients[0].client.sw_if_index, self.pg3.sw_if_index)
+        self.assertEqual(clients[0].lease.sw_if_index, self.pg3.sw_if_index)
         self.assertEqual(clients[0].client.hostname, hostname)
         self.assertEqual(clients[0].lease.hostname, hostname)
         # 0 = DISCOVER, 1 = REQUEST, 2 = BOUND
         self.assertEqual(clients[0].lease.state, 2)
         self.assertEqual(clients[0].lease.mask_width, 24)
-        self.assertEqual(str(clients[0].lease.router_address),
-                         self.pg3.remote_hosts[1].ip4)
-        self.assertEqual(str(clients[0].lease.host_address),
-                         self.pg3.remote_hosts[3].ip4)
+        self.assertEqual(
+            str(clients[0].lease.router_address), self.pg3.remote_hosts[1].ip4
+        )
+        self.assertEqual(
+            str(clients[0].lease.host_address), self.pg3.remote_hosts[3].ip4
+        )
 
         #
         # remove the DHCP config
@@ -1577,39 +1679,51 @@ class TestDHCP(VppTestCase):
         # Send back on offer with requested lease time, expect the request
         #
         lease_time = 1
-        p_offer = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                   IP(src=self.pg3.remote_ip4, dst='255.255.255.255') /
-                   UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                   BOOTP(op=1,
-                         yiaddr=self.pg3.local_ip4,
-                         chaddr=mac_pton(self.pg3.local_mac)) /
-                   DHCP(options=[('message-type', 'offer'),
-                                 ('server_id', self.pg3.remote_ip4),
-                                 ('lease_time', lease_time),
-                                 'end']))
+        p_offer = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst="255.255.255.255")
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1, yiaddr=self.pg3.local_ip4, chaddr=mac_pton(self.pg3.local_mac)
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "offer"),
+                    ("server_id", self.pg3.remote_ip4),
+                    ("lease_time", lease_time),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_offer)
         self.pg_enable_capture(self.pg_interfaces)
         self.pg_start()
 
         rx = self.pg3.get_capture(1)
-        self.verify_orig_dhcp_request(rx[0], self.pg3, hostname,
-                                      self.pg3.local_ip4)
+        self.verify_orig_dhcp_request(rx[0], self.pg3, hostname, self.pg3.local_ip4)
 
         #
         # Send an acknowledgment
         #
-        p_ack = (Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac) /
-                 IP(src=self.pg3.remote_ip4, dst='255.255.255.255') /
-                 UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) /
-                 BOOTP(op=1, yiaddr=self.pg3.local_ip4,
-                       chaddr=mac_pton(self.pg3.local_mac)) /
-                 DHCP(options=[('message-type', 'ack'),
-                               ('subnet_mask', '255.255.255.0'),
-                               ('router', self.pg3.remote_ip4),
-                               ('server_id', self.pg3.remote_ip4),
-                               ('lease_time', lease_time),
-                               'end']))
+        p_ack = (
+            Ether(dst=self.pg3.local_mac, src=self.pg3.remote_mac)
+            / IP(src=self.pg3.remote_ip4, dst="255.255.255.255")
+            / UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT)
+            / BOOTP(
+                op=1, yiaddr=self.pg3.local_ip4, chaddr=mac_pton(self.pg3.local_mac)
+            )
+            / DHCP(
+                options=[
+                    ("message-type", "ack"),
+                    ("subnet_mask", "255.255.255.0"),
+                    ("router", self.pg3.remote_ip4),
+                    ("server_id", self.pg3.remote_ip4),
+                    ("lease_time", lease_time),
+                    "end",
+                ]
+            )
+        )
 
         self.pg3.add_stream(p_ack)
         self.pg_enable_capture(self.pg_interfaces)
@@ -1641,11 +1755,11 @@ class TestDHCP(VppTestCase):
         Client.remove_vpp_config()
 
     def test_dhcp_client_vlan(self):
-        """ DHCP Client w/ VLAN"""
+        """DHCP Client w/ VLAN"""
 
         vdscp = VppEnum.vl_api_ip_dscp_t
         vqos = VppEnum.vl_api_qos_source_t
-        hostname = 'universal-dp'
+        hostname = "universal-dp"
 
         self.pg_enable_capture(self.pg_interfaces)
 
@@ -1653,24 +1767,20 @@ class TestDHCP(VppTestCase):
         vlan_100.admin_up()
 
         output = [scapy.compat.chb(4)] * 256
-        os = b''.join(output)
-        rows = [{'outputs': os},
-                {'outputs': os},
-                {'outputs': os},
-                {'outputs': os}]
+        os = b"".join(output)
+        rows = [{"outputs": os}, {"outputs": os}, {"outputs": os}, {"outputs": os}]
 
         qem1 = VppQosEgressMap(self, 1, rows).add_vpp_config()
-        qm1 = VppQosMark(self, vlan_100, qem1,
-                         vqos.QOS_API_SOURCE_VLAN).add_vpp_config()
+        qm1 = VppQosMark(
+            self, vlan_100, qem1, vqos.QOS_API_SOURCE_VLAN
+        ).add_vpp_config()
 
         #
         # Configure DHCP client on PG3 and capture the discover sent
         #
         Client = VppDHCPClient(
-            self,
-            vlan_100.sw_if_index,
-            hostname,
-            dscp=vdscp.IP_API_DSCP_EF)
+            self, vlan_100.sw_if_index, hostname, dscp=vdscp.IP_API_DSCP_EF
+        )
         Client.add_vpp_config()
 
         rx = self.pg3.get_capture(1)
@@ -1678,9 +1788,10 @@ class TestDHCP(VppTestCase):
         self.assertEqual(rx[0][Dot1Q].vlan, 100)
         self.assertEqual(rx[0][Dot1Q].prio, 2)
 
-        self.verify_orig_dhcp_discover(rx[0], self.pg3, hostname,
-                                       dscp=vdscp.IP_API_DSCP_EF)
+        self.verify_orig_dhcp_discover(
+            rx[0], self.pg3, hostname, dscp=vdscp.IP_API_DSCP_EF
+        )
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     unittest.main(testRunner=VppTestRunner)