Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

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 :)