Running pycodestyle on the latest version of Python 3.7 is giving the following future warning:
/usr/local/lib/python3.7/site-packages/pycodestyle.py:113: FutureWarning: Possible nested set at position 1
EXTRANEOUS_WHITESPACE_REGEX = re.compile(r'[[({] | []}),;:]')
In the future, please search closed and open issues before creating new ones that are duplicates.
https://github.com/PyCQA/pycodestyle/pull/735
https://github.com/PyCQA/pycodestyle/issues/728