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Python

Posted by lin huang
lin huang
4,284 Points

what is wrong with is instance()?

def combiner(mylist): sum = 0 str ="" for item in mylist: if isinstance(item,str): str += item elif isinstance(item,(int,float)): sum += item else: pass return str+str(sum)

instances.py 
def combiner(mylist):
    sum = 0
    str =""
    for item in mylist:
        if isinstance(item,str):
            str += item
        elif isinstance(item,(int,float)):
            sum += item
        else:
            pass
    return str+str(sum)

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,426 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,426 Points

Be careful of your variable name choices. By using str as a variable choice the code is overriding the local reference to the build-in type str. This means at the str + str(sum) statement, you are really trying to do "abcde" + "abcde"(sum).

:point_right: rename variable str to a non-builtin keyword