Skip Pycodestyle when ran with Py3 (#6972)
Skip Pycodestyle when ran with Py3 (#6972)

`long` is no longer in the std lib of Python 3, so pycodestyle was complaining about an invalid keyword.
tdyas/pants,benjyw/pants,benjyw/pants,wisechengyi/pants,twitter/pants,jsirois/pants,benjyw/pants,pantsbuild/pants,benjyw/pants,tdyas/pants,wisechengyi/pants,jsirois/pants,pantsbuild/pants,twitter/pants,benjyw/pants,twitter/pants,wisechengyi/pants,wisechengyi/pants,tdyas/pants,wisechengyi/pants,pantsbuild/pants,twitter/pants,tdyas/pants,tdyas/pants,tdyas/pants,wisechengyi/pants,twitter/pants,pantsbuild/pants,tdyas/pants,twitter/pants,benjyw/pants,twitter/pants,pantsbuild/pants,jsirois/pants,wisechengyi/pants,wisechengyi/pants,twitter/pants,tdyas/pants,pantsbuild/pants,wisechengyi/pants,benjyw/pants,twitter/pants,tdyas/pants,pantsbuild/pants