Fix lint errors

3 jobs for ext/devel/wp4c-execution-list-filter in 1 minute and 58 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Static Test
passed #2381
SonarQube

00:01:58

failed #2380
lint

00:01:09

 
  Integration Test
skipped #2382
api-test
 
Name Stage Failure
failed
lint Static Test There is an unknown failure, please try again
Successfully installed astroid-1.5.2 chardet-3.0.2 coverage-4.4 doc8-0.8.0 isort-4.2.5 lazy-object-proxy-1.3.1 mccabe-0.6.1 mypy-lang-0.4.6 pbr-3.0.0 pylint-1.7.1 restructuredtext-lint-1.0.1 stevedore-1.21.0 vulture-0.14 wrapt-1.10.10
$ chmod 755 run_tests.sh && ./run_tests.sh
************* Module zoe_api.rest_api.execution
W:165,12: Redefining built-in 'filter' (redefined-builtin)

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Your code has been rated at 10.00/10

ERROR: Job failed: exit code 1