[skip changelog] Resolve impossible to satisfy Flake8 configuration

[per1234]

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• The PR has no duplicates (please search among the Pull Requests
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• Tests for the changes have been added (for bug fixes / features)
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• What kind of change does this PR introduce?

Bug fix.

• What is the current behavior?

Flake8/pycodestyle has a pair of mutually exclusive checks:

• W503: line break before binary operator
• W504: line break after binary operator

Having both these checks enabled results in a failed check when there is a line break at a binary operator, which can't be
resolved by moving the operator.

if (
    some_long_condition
    and some_other_long_condition
):

fails the W503 check.

if (
    some_long_condition and
    some_other_long_condition
):

fails the W504 check.

• What is the new behavior?

PEP 8 recommends line break before the binary operator, so the logical choice of which of the two checks to keep is W504.

Flake8 is now configured to ignore W503 and it is possible to format the Python code in a way that will pass the check.

• Does this PR introduce a breaking change?

No