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

Posted by Sarah Cordier
Sarah Cordier
1,399 Points

TRY AND EXCEPT

I have been stuck on this for days and I can't seem to get help from my classmates. I am very confused about how to use try and except blocks. If someone could help explain, that would be great. Thanks!

trial.py 
def add (num1, num2):
try:
   return float(num1) + float(num2)
except ValueError:
   return none

2 Answers

Anish Walawalkar
Anish Walawalkar
8,534 Points
Anish Walawalkar
Anish Walawalkar
8,534 Points

Hey Sarah, you made 2 very small mistakes:

  1. You forgot to indent the block of code inside the add function
  2. It should be None not none

in code it looks like this:

def add(num1, num2):
    try:
        return float(num1) + float(num2)
    except:
        return None

And you used the try and perfect blocks perfectly. As the names suggest you run some piece of code in the try block which may or may not raise an exception. when it does raise an exception it enters the except block to perform the exception handing code. :)

tomasvukasovic
tomasvukasovic
24,022 Points
tomasvukasovic
tomasvukasovic
24,022 Points

First of all they should be indented, and Try and except is used to run a piece of code that you know can through an error and if that error happens then you can run another piece of code regarding that error, like printing a message that says " you can type letters only numbers "