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

Posted by Cool Broz
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Cool Broz
Python Web Development Techdegree Student 724 Points

try and except

challenge task 3

trial.py 
def add(num1,num2):
    return (num1+num2)

sum = add(2,2)
print(sum)

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

sum = add(2,2)
print(sum)

1 Answer

Henrik Christensen
seal-mask
.a{fill-rule:evenodd;}techdegree
Henrik Christensen
Python Web Development Techdegree Student 38,322 Points
Henrik Christensen
.a{fill-rule:evenodd;}techdegree
Henrik Christensen
Python Web Development Techdegree Student 38,322 Points

3rd time answering this.

This is how it could look

# make a new function 'add'
# 'add' should take two arguments
def add(num1, num2):
    # add a 'try' block
    try:
        # convert arguments to floats
        num1 = float(num1)
        num2 = float(num2)
    # then add an except to catch the possible 'ValueError'
    except ValueError:
        # inside the except block 'return None'
        return None
    # if following the structure from the videos add an 'else' for final return
    else:
        # add then together and return the total
        return num1 + num2
Cool Broz
.a{fill-rule:evenodd;}techdegree
Cool Broz
Python Web Development Techdegree Student 724 Points

there is nameError : 'add' is not defined