Tool to convert Python code to be PEP8 compliant

You can use autopep8! Whilst you make yourself a cup of coffee this tool happily removes all those pesky PEP8 violations which don’t change the meaning of the code.

Install it via pip:

pip install autopep8

Apply this to a specific file:

autopep8 py_file --in-place

or to your project (recursively), the verbose option gives you some feedback of how it’s going:

autopep8 project_dir --recursive --in-place --pep8-passes 2000 --verbose

Note: Sometimes the default of 100 passes isn’t enough, I set it to 2000 as it’s reasonably high and will catch all but the most troublesome files (it stops passing once it finds no resolvable pep8 infractions)…

At this point I suggest retesting and doing a commit!

If you want “full” PEP8 compliance: one tactic I’ve used is to run autopep8 as above, then run PEP8, which prints the remaining violations (file, line number, and what):

pep8 project_dir --ignore=E501

and manually change these individually (e.g. E712s – comparison with boolean).

Note: autopep8 offers an --aggressive argument (to ruthlessly “fix” these meaning-changing violations), but beware if you do use aggressive you may have to debug… (e.g. in numpy/pandas True == np.bool_(True) but not True is np.bool_(True)!)

You can check how many violations of each type (before and after):

pep8 --quiet --statistics .

Note: I consider E501s (line too long) are a special case as there will probably be a lot of these in your code and sometimes these are not corrected by autopep8.

As an example, I applied this technique to the pandas code base.

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