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

Matthew Cooper
Matthew Cooper
2,785 Points
Posted by Matthew Cooper
Matthew Cooper
2,785 Points

try and except

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 
try:
num1 = int(input("number: "))
num2 = int(input("number: "))
except ValueError:
    return(None)
else:
    return(float(num1))+float(num2)

1 Answer

Jesse Schoonveld
Jesse Schoonveld
2,943 Points
Jesse Schoonveld
Jesse Schoonveld
2,943 Points

It's asking you to make a function that adds two arguments together. 

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