Update flake8 to 3.4.1

[pyup-bot]

There's a new version of flake8 available. You are currently using 3.3.0. I have updated it to 3.4.1

These links might come in handy: PyPI | Changelog | Repo

Changelog

3.4.1

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You can view the 3.4.1 milestone_ on GitLab for more details.

• Fix minor regression when users specify only a --select list with items in the enabled/extended select list. (See also GitLab354_)

.. all links .. _3.4.1 milestone: https://gitlab.com/pycqa/flake8/milestones/19

.. issue links .. _GitLab354: https://gitlab.com/pycqa/flake8/issues/354

.. merge request links

3.4.0

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You can view the 3.4.0 milestone_ on GitLab for more details.

• Refine logic around --select and --ignore when combined with the default values for each. (See also GitLab318_)

• Handle spaces as an alternate separate for error codes, e.g., --ignore 'E123 E234'. (See also GitLab329_)

• Filter out empty select and ignore codes, e.g., --ignore E123,,E234. (See also GitLab330_)

• Specify dependencies appropriately in setup.py (See also Gitlab341_)

• Fix bug in parsing --quiet and --verbose from config files. (See also GitLab!193_)

• Remove unused import of os in the git hook template (See also GitLab!194_)

.. all links .. _3.4.0 milestone: https://gitlab.com/pycqa/flake8/milestones/18

.. issue links .. _GitLab318: https://gitlab.com/pycqa/flake8/issues/318 .. _GitLab329: https://gitlab.com/pycqa/flake8/issues/329 .. _GitLab330: https://gitlab.com/pycqa/flake8/issues/330 .. _GitLab341: https://gitlab.com/pycqa/flake8/issues/341

.. merge request links .. _GitLab!193: https://gitlab.com/pycqa/flake8/merge_requests/193 .. _GitLab!194: https://gitlab.com/pycqa/flake8/merge_requests/194

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖