The development of this plugin was made live during a webinar. You can watch a recording here: PyCharm Webinar about Flake8.
This plugin adds support for flake8
# noqa and
# flake8: noqa.
With this plugin installed PyCharm will now show error markers any more as long as one of the two markers are defined.
Previously you had to do this to remove warnings from both flake8 and PyCharm:
Now you can just use flake8's markers: