1 files changed, 36 insertions, 3 deletions
diff --git a/resources/libraries/python/IPv4Setup.py b/resources/libraries/python/IPv4Setup.py
index d4be4c602a..07089025b0 100644
--- a/resources/libraries/python/IPv4Setup.py
+++ b/resources/libraries/python/IPv4Setup.py
@@ -34,6 +34,15 @@ class IPv4Node(object):
 
     @staticmethod
     def _get_netmask(prefix_length):
+        """Convert IPv4 network prefix length into IPV4 network mask.
+
+        :param prefix_length: Length of network prefix.
+        :type prefix_length: int
+
+        :return: Network mask.
+        :rtype: str
+        """
+
         bits = 0xffffffff ^ (1 << 32 - prefix_length) - 1
         return inet_ntoa(pack('>I', bits))
 
@@ -112,9 +121,25 @@ class Tg(IPv4Node):
         super(Tg, self).__init__(node_info)
 
     def _execute(self, cmd):
+        """Executes the specified command on TG using SSH.
+
+        :param cmd: Command to be executed.
+        :type cmd: str
+
+        :return: Content of stdout and stderr returned by command.
+        :rtype: tuple
+        """
         return exec_cmd_no_error(self.node_info, cmd)
 
     def _sudo_execute(self, cmd):
+        """Executes the specified command with sudo on TG using SSH.
+
+        :param cmd: Command to be executed.
+        :type cmd: str
+
+        :return: Content of stdout and stderr returned by command.
+        :rtype: tuple
+        """
         return exec_cmd_no_error(self.node_info, cmd, sudo=True)
 
     def set_ip(self, interface, address, prefix_length):
@@ -135,6 +160,13 @@ class Tg(IPv4Node):
                            format(network, prefix_length))
 
     def arp_ping(self, destination_address, source_interface):
+        """Execute 'arping' command to send one ARP packet from the TG node.
+
+        :param destination_address: Destination IP address for the ARP packet.
+        :param source_interface: Name of an interface to send ARP packet from.
+        :type destination_address: str
+        :type source_interface: str
+        """
         self._sudo_execute('arping -c 1 -I {} {}'.format(source_interface,
                                                          destination_address))
 
@@ -207,6 +239,7 @@ class Dut(IPv4Node):
                       sw_if_index=self.get_sw_if_index(interface))
 
     def arp_ping(self, destination_address, source_interface):
+        """Does nothing."""
         pass
 
     def flush_ip_addresses(self, interface):
@@ -286,9 +319,9 @@ class IPv4Setup(object):
                 host = port.get('node')
                 dev = port.get('if')
                 if host == node['host'] and dev == interface:
-                    ip = port.get('addr')
-                    if ip is not None:
-                        return ip
+                    ip_addr = port.get('addr')
+                    if ip_addr is not None:
+                        return ip_addr
                     else:
                         raise Exception(
                             'Node {n} port {p} IPv4 address is not set'.format(