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

Posted by Chunxiao Li
Chunxiao Li
1,091 Points

Try block

I have problems on the question below: 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(n1,n2):
    try:
          except ValueError:
            return None
    else:
        n1 = float(n1)
        n2 = float(n2)
        return(n1+n2)

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

You have the right bits, but in the wrong places.

The float conversions need to be done inside the try for any exceptions they generate to be caught.

Also, check your indentation, a try, except and else should all start in the same column.