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Python Python Basics (Retired) Putting the "Fun" Back in "Function" Functions

Posted by Fredrik August Madsen-Malmo
Fredrik August Madsen-Malmo
16,261 Points

Putting the "Fun" Back in "Function" | Stage 5 - can't write str to text stream

list1=[1,2,3]

def add_list(list):
    sum = 0 
    for number in list:
        sum = sum + number
    return sum

b= add_list(list1)
print(b)

When I run this code, I get an error saying "can't write str to text stream". I see no reason for this code not to pass, so I'm wondering if I'm doing something wrong.

Thanks, Fredrik A. Madsen-Malmo

2 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

it may be because your function add_list returns an integer which would have to be converted to a string before it could be printed.

You dont need to call your function or print anything out. simply define the function. thats all you need. adding anything else may cause the challenge engine to not accept your code:

your function is correct. so all you need to type for task 1 is:

def add_list(list):
    sum = 0 
    for number in list:
        sum = sum + number
    return sum

note: list is keyword in python so you may want to change your parameter name to something different:

def add_list(some_list):
    sum = 0 
    for number in some_list:
        sum = sum + number
    return sum
Fredrik August Madsen-Malmo
Fredrik August Madsen-Malmo
16,261 Points

Thanks a lot! I will try your version and let you know if it works.

Kenneth Love
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

.format() converts things to strings, so the wrapping shouldn't be required.

Our CC engine is having some issues the last day or two, so that's likely the cause of it malfunctioning.

Fredrik August Madsen-Malmo
Fredrik August Madsen-Malmo
16,261 Points

Thanks.

Kenneth Love
STAFF
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Just tested your answer and it gets past the first step of the CC, so you should be good to try and finish it.