Fix various pylint violations

+ SchedUtils.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
+ VatHistory.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
+ VppCounters.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
+ Memif.py:
++ Do not use `len(SEQUENCE)` to determine if a sequence is empty
++ Either all return statements in a function should return an expression,
   or none of them should.
++ Update :return: on possible None.
+ Classify.py: Unnecessary "else" after "return"
+ ContainerUtils.py: Useless super delegation in method '__init__'
+ CpuUtils.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
+ DropRateSearch.py: Either all return statements in a function
  should return an expression, or none of them should.
+ IPv4NodeAddress.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
++ Also improve docstrings.
+ IPv4Setup.py: Useless super delegation in method '__init__'
+ IPv6Setup.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
++ Also improve docstrings.
+ IPv6Setup.py: standard import "from ipaddress import IPv6Network"
  should be placed before "from robot.api import logger"
+ MacSwap.py: Trailing newlines
+ NATUtil.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
+ NodePath.py: Unnecessary "else" after "return"
+ Tap.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
+ topology.py: Either all return statements in a function
  should return an expression, or none of them should.
+ topology.py: Unnecessary "else" after "return"
++ Do not use `len(SEQUENCE)` to determine if a sequence is empty
++ Improve docstrings
+ DUTSetup.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
++ Also do not compare int(ret_code) just to access zero-ness.
+ ssh.py: Do not use `len(SEQUENCE)` to determine if a sequence is empty
+ InterfaceUtil.py: Unnecessary "else" after "return"

Change-Id: Iba4244aa79661ee7df15fed5c7c6dbf04dfa88b2
Signed-off-by: Vratko Polak <vrpolak@cisco.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/resources/libraries/python/VatHistory.py b/resources/libraries/python/VatHistory.py
index e273746f9b..ffc1644f1b 100644
--- a/resources/libraries/python/VatHistory.py
+++ b/resources/libraries/python/VatHistory.py
@@ -71,12 +71,12 @@ class VatHistory(object):
         :type node: dict
         """
         if node['type'] == NodeType.DUT:
-            sequence = "\nno VAT command executed"\
-                if len(DICT__DUTS_VAT_HISTORY[node['host']]) == 0\
-                else "".join("\n{}".format(cmd)
-                             for cmd in DICT__DUTS_VAT_HISTORY[node['host']])
-            logger.trace("{0} VAT command history:{1}\n".
-                         format(node['host'], sequence))
+            sequence = "\nno VAT command executed"
+            if DICT__DUTS_VAT_HISTORY[node['host']]:
+                sequence = "".join(["\n{}".format(
+                    cmd) for cmd in DICT__DUTS_VAT_HISTORY[node['host']]])
+            logger.trace(
+                "{0} VAT command history:{1}\n".format(node['host'], sequence))
 
     @staticmethod
     def show_vat_history_on_all_duts(nodes):