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Python Python Basics (2015) Logic in Python Try and Except

Matt Wolf
Matt Wolf
2,225 Points

NameError?

It says "NameError: name 'add' is not defined". Why am I getting this error?

trial.py
def add(a,b):
    try:
        a = float(a)
        b = float(b)
    except ValueError:
        return none
    else:
        return a+b

2 Answers

Umesh Ravji
Umesh Ravji
42,362 Points

Hi Matt, you have to return None not none. Python is case sensitive :)

def add(a,b):
    try:
        a = float(a)
        b = float(b)
    except ValueError:
        return None
    else:
        return a+b

Pycharm gives me NameError: name 'none' is not defined when trying to call the function. I'm assuming the 'answer checking engine' is giving back add is not defined because the misspelling prevents it from running correctly.

Matt Wolf
Matt Wolf
2,225 Points

Thanks Umesh - that's exactly right. I figured it out and that was the issue. Thanks