Question

I am getting an error from this Python code:

with open('names') as f:
    names = f.read()
    names = names.split('\n')
    names.pop(len(names) - 1)
    names = shuffle(names)
    f.close()

assert len(names) > 100

Error:

Python: TypeError: object of type 'NoneType' has no len()

The assert statement is throwing this error, what am I doing wrong?

Answer 1

shuffle(names) is an in-place operation. Drop the assignment.

This function returns None and that’s why you have the error:

TypeError: object of type 'NoneType' has no len()