PEP8 is a StyleGuide for Python. A tool that validates code against it goes by the same name. Using pep8 helps you conform to common coding standard and at the same time avoid some 'silly' mistakes. $ pep8 main.py main.py:4:1: E122 continuation line missing indentation or outdented main.py:5:1: E122 continuation line missing indentation or outdented main.py:6:1: E122 continuation line missing indentation or outdented main.py:10:1: W391 blank line at end of file This is a short article. Please extend it!