Видео ютуба по тегу Attributeerror: 'Nonetype' Object Has No Attribute 'Lower' Python3

Solving the AttributeError: 'NoneType' object has no attribute 'lower' in Python 3
Solving the AttributeError: 'NoneType' object has no attribute 'lower' in Python 3
Solving NoneType Errors in Python: A Guide to Handling .lower() Method on Lemmas
Solving NoneType Errors in Python: A Guide to Handling .lower() Method on Lemmas