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Python Python Collections (2016, retired 2019) Tuples Combo

Benjamin Bradshaw
Benjamin Bradshaw
3,208 Points
Posted by Benjamin Bradshaw
Benjamin Bradshaw
3,208 Points

I'm Stumped

any pointers? am i just way off?

combo.py 
# combo([1, 2, 3], 'abc')
# Output:
# [(1, 'a'), (2, 'b'), (3, 'c')]


def combo(arg1, arg2):
    list1 = []
    for abstract in range(len(arg1)):
        double_tuple = list1.append(arg1[abstract], arg2[abstract])
    return double_tuple

2 Answers

Ryan S
Ryan S
27,276 Points
Ryan S
Ryan S
27,276 Points

Hey Benjamin,

You are actually quite close. The only issue is the way you are appending items to double_tuple.

The append() method doesn't actually return a value, so on each iteration of your loop, nothing is getting assigned to double_tuple. When all is said and done, it will have no value and will be of type "NoneType".

list1, however, will have a value so you might as well just return it. And you can get rid of double_tuple while you're at it since you won't need an intermediary variable.

Also, keep in mind that append() can only take one argument so you will need to wrap your arguments in parentheses and pass in a single tuple, which is what the challenge is asking for.

def combo(arg1, arg2):
    list1 = []
    for abstract in range(len(arg1)):
        list1.append((arg1[abstract], arg2[abstract]))
    return list1

Hope this helps.

seong lee
seong lee
4,503 Points
seong lee
seong lee
4,503 Points

wow this explanation was the best explanation i have ever heard about this challenge. It also helped me to. thank you.

Clifford Gagliardo
Clifford Gagliardo
Courses Plus Student 15,069 Points

I do not understand why the length of the first argument has to be found. How does this help solve the problem?

Clifford Gagliardo
Clifford Gagliardo
Courses Plus Student 15,069 Points

Also, I don't understand why you only need one iterating variable and not a second one to access the second argument.

Sorry for all the questions, but I am quite new to this and I only understand half of why this solution works.