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Start your free trial###### Corey Chattin

777 Points# Make a function named add_list that takes a list. I am stuck help!

Make a function named add_list that takes a list. The function should then add all of the items in the list together and return the total. Assume the list contains only numbers. You'll probably want to use a for loop. You will not need to use input().

I can't seem to get past this, what am I doing wrong? I'd love to continue the content but I am trapped!

## 9 Answers

###### Robert Richey

Courses Plus Student 16,352 PointsHi Corey,

Let's break this down together and tackle each component separately.

- Make a function named add_list that takes a list
- The function should then add all of the items in the list together
- Return the total

```
def add_list(list_of_numbers):
# create a variable to holder the sum of values from the list - possibly call it counter
# loop over each number in list_of_numbers
# add current number in list to counter
# return counter
```

Let me know if this helps or not.

Cheers

###### Corey Chattin

777 PointsThis started me thinking: I am so furstrated and feel like a complete idiot. I have this...

```
list_of_numbers = [1, 2, 3]
def add_list(list_of_numbers):
counter = []
for item in list_of_numbers:
counter.append(item)
```

###### Robert Richey

Courses Plus Student 16,352 PointsEdited your post to display python with proper markdown. Your markdown was really close, just had an extra p in python (Ppython) and there needed to be a blank line above the markdown. Give me a few minutes and I'll take a closer look at your code.

###### Robert Richey

Courses Plus Student 16,352 PointsThere is no need to define a list of numbers - when the challenge is run, it will supply it's own list to your function.

Your code is pretty close to being good.

- The counter variable will just be adding numbers together during each loop iteration, so this variable can be a number that starts at 0.
- The for loop declaration looks good.
- Inside the loop, for each item, add item to counter.
- Finally, at the end of the function, don't forget to return counter - which holds the sum of values from the number list.

```
def add_list(list_of_numbers):
counter = 0
for item in list_of_numbers:
# add to counter the value of item
return counter
```

So, just one line of code left to figure out. I'm confident you can do this.

Kind Regards

###### Corey Chattin

777 Pointsyeah I got it!

```
def add_list(list_of_numbers):
counter = 0
for item in list_of_numbers:
counter = counter + item
return counter
```

###### Robert Richey

Courses Plus Student 16,352 PointsAwesome! It's a great feeling to work through and solve a problem.

###### Corey Chattin

777 PointsSo I have this:

```
def add_list(list_of_numbers):
counter = 0
for item in list_of_numbers:
counter = item + counter
return counter
```

###### Robert Richey

Courses Plus Student 16,352 PointsYour code looks great! Only one small issue - the return statement is indented too far. The program thinks it's the last line of execution within your for loop - so the loop iterates once and then returns counter. Dedent return and you should pass the challenge (the level of indentation is a big deal in python).

###### Corey Chattin

777 PointsTried this and every indent inbetween:

```
def add_list(list_of_numbers):
counter = 0
for item in list_of_numbers:
counter + item
return counter
```

The version of the code I posted above was returning an error of "Bummer! add_list didn't return the right answer. Got 0 when adding [1, 2, 3], expected 6."

###### Corey Chattin

777 PointsThank you very much for your help today Robert! :)

###### Neil Gordon

8,823 Pointsthis is what worked for me

```
list_of_numbers = [1,2,3]
def add_list(list_of_numbers):
for item in list_of_numbers:
counter = 3
counter = counter + item
return counter
```

###### Thomas Ton

9,836 PointsCheck this out

```
def add_list(number_list):
return sum(number_list)
```