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# I feel I'm doing something very wrong but I'm not sure what... return("the sum of [arg] is Y")

I know what I want it to do but not how to make it work... lol

functions.py
```# add_list([1, 2, 3]) should return 6
# summarize([1, 2, 3]) should return "The sum of [1, 2, 3] is 6."
# Note: both functions will only take *one* argument each.

return(sum(num))

def summarize(numb):
return("The sum of %d is %d."(numb, sum(numb))
``` MOD

In your `summarize` function, you are casting the `numb` argument as a decimal value using '%d'. Instead, cast it as a string:

```def summarize(numb):
return("The sum of %s is %d."(numb, sum(numb)))

# or use the '.format' method
def summarize(numb):
return("The sum of {} is {}.".format(numb, sum(numb)))
```

Additionally, this challenge intends for you to solve the `add_list` challenge using a loop instead of the `sum` function.

EDIT: added missing closing paren as mentioned by Michel van Essen

Thank you very much. ```def add_list(lst):
# set our current total to 0.
total = 0
# for each item in the passed-in argument 'lst'...
for item in lst:
# added each item to the total
total = total + item
# return current total value This does however illustrate the intended solution for `add_list` that uses a loop instead of the `sum` function