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

I'm not sure what i'm doing wrong on this challenge.

I don't know if we were supposed to create an input to get the numbers? It doesn't say that we need to, but I can't get the correct answer here. If anyone can explain what i'm doing wrong, i'd appreciate it.


def add(one, two):
    one = float(one)
    two = float(two)
  except ValueError:
    return ("None.")
    return (one + two)

ad = add(3,3)

1 Answer

Steven Parker
Steven Parker
215,959 Points

You're really close! Here are a few hints:

  • for the challenge, just define the function, don't call it yourself
  • you also won't need to print anything
  • None is a special Python keyword. Don't add a period or put quotes around it (that makes it an ordinary string).
  • FYI: you don't need parentheses after a return (but they don't hurt anything)

ahh! Thank you. I got it now.

Hi Steven, got the same error as Frank here but I'm not sure why since I've wrote it in the right manner

def add(one,two):


numbers = float(one) + float(two)

except ValueError: return None else: return numbers