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Start your free trial###### Patrick Nieto

3,032 Points# I am having trouble with task 1 in functions.py. I am not sure how to correctly write the function in order to return 6.

What am I doing wrong here?

I don't understand what I should be calling the items in the list? should I be referring to them as num? Also, I have a feeling the argument sum is incorrectly used

```
num_list = []
def add_list(sum):
for num in num_list:
sum = sum + num
print(sum)
# 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.
```

## 2 Answers

###### Dan Johnson

40,532 PointsYou have the right idea on how to sum the list, but you're actually being passed in the list of numbers instead of a starting sum (if you were wondering why sum was highlighted, it's because it's the name of a built-in function). So here's an outline:

```
# Expect a list of numbers to be passed in (you can use a different name if you'd prefer).
def add_list(numbers):
# Create a variable local to the function for the sum, starting at 0
# Loop through and add to the total sum like you did before
# Return the sum
```

###### Charlie Thomas

40,856 PointsHi! First off your argument should the list of numbers not sum since the function is using the list of numbers. Then inside your function make sure you set sum to 0 before your for loop. Finally, you need to return sum not print it. Your code should look similar to mine. If you want me to try and explain anything better - I'm not great at explaining stuff - comment below and I'll try.

```
def add_list(num_list):
sum = 0
for num in num_list:
sum += num
return sum
```

###### Patrick Nieto

3,032 PointsThank you for your help!

## Patrick Nieto

3,032 Points## Patrick Nieto

3,032 PointsThank you! That outline really helped!