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

Posted by Daron George
Daron George
700 Points

Python Question

I need help figuring out what I am doing wrong.

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.

trial.py 
def add(ab1,ab2):
    try:
        return float(ab1) + float(ab2)
except ValueError:
        return ('none')
else:
        return float(ab1) + float(ab2)

1 Answer

Jeremiah Bushau
Jeremiah Bushau
24,061 Points

Hey there, looks like you need to fix the indentation of the except and else blocks. Also instead of returning 'none' in your except block return None. Here is a helpful stackoverflow question about the None value http://stackoverflow.com/questions/19473185/what-is-a-none-value.

def add(ab1,ab2):
    try:
        return float(ab1) + float(ab2)
    except ValueError:
        return None
    else:
        return float(ab1) + float(ab2)
Daron George
Daron George
700 Points

Thanks for your help!