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

Suresh Unnithan
Suresh Unnithan
2,718 Points

how to have final return of added floats on the else block?

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( item1 ,item2):
    try:
 return(float(item1) + float(item2))
except ValueError:
   return =None
else:
   return(item1+item2)

1 Answer

Jennifer Nordell
STAFF
Jennifer Nordell
Treehouse Staff

Hi there! There are a couple of things going on here. First, your indentation is off. Remember, Python uses indentation to determine what constitutes the start and end of a block of code. If your indentation is incorrect, it will not understand what you mean. Secondly, you have a syntax error.

You typed return = None but you meant to type just return None. The equals sign is causing the syntax error there.

Your except, and else should match up to where your try is. Note that your try is indented correctly at present. The return statements below them should be indented once. Here's some pseudocode to help you figure out the indentation:

def my_function():
    try:
       return something
    except ValueError:
       return something_else
    else:
       return another_thing

Hope this helps! :sparkles:

Suresh Unnithan
Suresh Unnithan
2,718 Points

thank you for help. it was useful