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# Combo Code challenge question

Hi,

I solved this challenge in two different ways. Both deliver the desired result. However I feel like this could be further improved and made more efficient. Please check out both of my solutions and advice me on what I can improve and what I must NEVER do.

kind regards,

solution 1:

```def combo(list1, list2):
list = []

for (item1, item2) in zip(list1, list2):
list.append((item1, item2))
return list
combo([1, 2, 3], 'abc')
```

solution 2:

```def combo(list1, list2):
list = []

for value1, value2 in enumerate(list2):
list.append((value1+1, value2))
return list
combo([1, 2, 3], 'abc')
```

It might appear to do the same thing when tested using these particular arguments, but it will not do the same thing with other arguments, and it will not pass the challenge. Try pasting it into the challenge yourself and see! Or test both versions using: `combo('abc', [1, 2, 3])` or `combo('test', 'this')`.
The key takeaway is in Steven's answer, but regarding your first soution (which is fine), you can also construct a list from the zip object with the built-in `list()` method, so the whole function body will be just one line:
```def combo(list1, list2):