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

Gabriel Ogbonnaya
Gabriel Ogbonnaya
1,701 Points
Posted by Gabriel Ogbonnaya
Gabriel Ogbonnaya
1,701 Points

What's wrong with the code

You're doing great! Just one more task but it's a bigger one. Right now, we turn everything into a float. That's great so long as we're getting numbers or numbers as a string. We should handle cases where we get a non-number, though. Add a try block before where you turn your arguments into floats. Then add an except to catch the possible ValueError. Inside the except block, return None. If you're following the structure from the videos, add an else: for your final return of the added floats.

trial.py 
def add(gain,mike):
    try:
    except ValueError:
        return(None)
    else:
        return(float(gain) + float(mike))
jonteamere
jonteamere
10,287 Points
jonteamere
jonteamere
10,287 Points

The 'return float' portion should be indented just after 'try:' Excellent job otherwise. Keep it up!

def add(gain, mike):
    try:
        return(float(gain) + float(mike))
    except ValueError:
        return(None)

1 Answer

Alex Koumparos
seal-mask
.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,887 Points
Alex Koumparos
.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,887 Points

HI Gabriel,

It looks like you're having some trouble with how try/except/else blocks work. I suggest you rewatch the The Exception To The Rule video which explains this concept.

Pay particular attention to what each component of the block means and why they exist - especially the try piece which in your code is empty.

If you're still confused after rewatching the video, let me know and I'll give you some more pointers.

Cheers

Alex