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

Posted by Adirek Satam
Adirek Satam
1,671 Points

code for challenge task 3 I want to know how to defind "try:" and how wrong this my code. thanks

code for challenge task 3 I want to know how to defind "try:" before or after "def". and how wrong this my code.thank you.

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

3 Answers

Russell Sawyer
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.a{fill-rule:evenodd;}techdegree
Russell Sawyer
Front End Web Development Techdegree Student 15,705 Points
Russell Sawyer
.a{fill-rule:evenodd;}techdegree
Russell Sawyer
Front End Web Development Techdegree Student 15,705 Points

You're pretty close. Your try: needs to be inside the function. The try just verifies that the numbers are not strings. If they are then the ValueError: will return None. else: return the sum of the floated numbers.

def add(num1, num2):
    try:
        num1 = float(num1)
        num2 = float(num2)
    except ValueError:
        return None
    else:
        return num1 + num2
Adirek Satam
Adirek Satam
1,671 Points
Adirek Satam
Adirek Satam
1,671 Points

thank you so much. and after "return" shound I use the parentheses around "None", "num1 + num2" or write the code same your code.

Russell Sawyer
seal-mask
.a{fill-rule:evenodd;}techdegree
Russell Sawyer
Front End Web Development Techdegree Student 15,705 Points
Russell Sawyer
.a{fill-rule:evenodd;}techdegree
Russell Sawyer
Front End Web Development Techdegree Student 15,705 Points

With return values you don't use parentheses. You do, however, use parentheses with print(). But in this challenge they are asking you to return the values.

Adirek Satam
Adirek Satam
1,671 Points
Adirek Satam
Adirek Satam
1,671 Points

thanks for your suggestion that help me a lot.