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

Posted by Austin Greed
.a{fill-rule:evenodd;}techdegree
Austin Greed
Python Web Development Techdegree Student 1,966 Points

the question is that use try and except block and return a value in the else block

i cant get where i am wrong

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

add(2,3)

1 Answer

Krishna Pratap Chouhan
Krishna Pratap Chouhan
15,191 Points
Krishna Pratap Chouhan
Krishna Pratap Chouhan
15,191 Points

Indentation Error;

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

add(2,3)
Austin Greed
.a{fill-rule:evenodd;}techdegree
Austin Greed
Python Web Development Techdegree Student 1,966 Points

how should i solve it??

Krishna Pratap Chouhan
Krishna Pratap Chouhan
15,191 Points

Let me give you an example of an block.

Generally in programming languages, blocks are everything inside '{' and '}'.

{
i am in first block.
{i am in second block but i am also in first block.
}
i am in first block
}

Similarly in python a block is recognized by tab/space before the line...

I am in main block
    Oh i am in other block, but child of main block
    i am still here
        i am in completely new child block
        i am still in completely new child block
i am again in main block

So for your code...

#start of a function 
def add(num1,num2):
    #this should be in the child block of 'def' so prefix all the lines with a tab
    try:
        #this is try block so another level of indentation
        num1 = float(num1)
        num2 = float(num2)
    except ValueError:
        return None
    else:
        return num1+num2

Let me know, if its still not clear.