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

Ján Pokorný
Ján Pokorný
1,031 Points

I don't know why this doesn't work... thank you for your help

watched the video three times

trial.py
def add(arg1, arg2)
try:
    arg1 = float(arg1)
    arg2 = float(arg2)
except ValueError:
    return(None)
else:
    return(arg1 + arg2)

1 Answer

Aaron Nolan
Aaron Nolan
5,714 Points

So you're answer is technically correct but you just have two simple problems.

First, you forgot the colon at the end of your first line, so it should look like so :

def add(arg1, arg2):

Second, tab spacing is very important to Python. Since you didn't tab in after the first line, that causes python to not see this as part of the method. So while the following will not build for you :

def add(arg1, arg2):
try:
    arg1 = float(arg1)
    arg2 = float(arg2)
except ValueError:
    return(None)
else:
    return(arg1 + arg2)

If you make sure the tab spacing is correct, it will build just fine :

def add(arg1, arg2):
    try:
        arg1 = float(arg1)
        arg2 = float(arg2)
    except ValueError:
        return(None)
    else:
        return(arg1 + arg2)

Hope this helps! Happy coding :)