CLN: pandas/io/parsers.py
- [ ] closes #xxxx
- [ ] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Slight clean-up of ``pandas/io/parsers.py``.
thanks @ivanovmg nice!