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Python Python Collections (Retired) Tuples Combo

Combo() Function That Returns List of Tuples

The error message I received was "Where's 'combo()'?" I've deleted the lines of code to see if I could isolate an error in one of the other lines, but the error messages didn't lead me anywhere.

# combo([1, 2, 3], 'abc')
# Output:
# [(1, 'a'), (2, 'b'), (3, 'c')]
# If you use .append(), you'll want to pass it a tuple of new values.

def combo(list1, list2):

    for item in list1:
        my_tuples_list.append(list1[item], list2[item])

    return my_tuples_list

2 Answers

Kourosh Raeen
Kourosh Raeen
23,733 Points

Hi matildadigital - Before starting the for loop define the list:

my_tuples_list = []

That will take care of the "Where's combo()?" error. But there are other issues with the code. The loop variable item holds the items in list1, but you're using it as in index for both lists. Try changing your loop to:

for index in range(len(list1)):

Now you can use index as an actual index of items in both lists.

Last issue is that you need to return a list of tuples so before doing the append use parenthesis to make a tuple out of the two items and then append the tuple to my_tuples_list.

matilda, yes, the error seems totally spurious. Here, try this:

def combo(iter1, iter2):
  combo_list = []
  for index, value in enumerate(iter1):
    tuple = value, iter2[index]
  return combo_list
4,442 Points

Thank you Jcorum! :)