Why do I get AttributeError: 'NoneType' object has no attribute 'something'?

Question

I keep getting an error that says

AttributeError: \'NoneType\' object has no attribute \'something\'

Answer 1

g.d.d.c. is right, but adding a very frequent example:

You might call this function in a recursive form. In that case, you might end up at null pointer or NoneType. In that case, you can get this error. So before accessing an attribute of that parameter check if it's not NoneType.