From reading this post I have found that there are some pseudo classes for 'valid' and 'invalid' input values introduced to HTML5. Is there a way I can mark an input field as invalid/valid from
I got this error from my code: ValueError: invalid literal for int() with base 10: ''. What does it mean? Why does it occur, and how can I fix it?
ValueError: invalid literal for int () with base 10: - Stack Overflow