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

Except block python challenge Task 3/3

I've tried everything, what am i missing here? I know else is probably not supposed to be there, that's just result of experimentation, but what else?

You're doing great! Just one more task but it's a bigger one. 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
def add(num1, num2):
    try:
         a = float(num1)
         b = float(num2)
         except ValueError:
            return none
    else:
        return num1 + num2

3 Answers

james south
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james south
Front End Web Development Techdegree Graduate 33,271 Points

you are close. first, your indentation is off. try, except and else should be at the same level of indentation. their respective bodies are then indented from that level

try
    body
except
    body
else
    body

next, in python it's None, not none. it might throw an error on that. finally, you are returning your un-casted parameters, not a and b which you have float casted in the try block. you could return a + b, or in the try just re-assign to num1 and num2 float casts of themselves, like num1 = float(num1).

understood! thanks!

def add(num1,num2): try: a = float(num1) b = float(num2) except ValueError: return None else: return num1+num2 I am having a similar issue :( please help

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