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Python

Derek Graham Chema
Derek Graham Chema
845 Points
Posted by Derek Graham Chema
Derek Graham Chema
845 Points

I find this problem to be super confusing, any help?

So i found the solution for this problem on the web, but my brain can't catch why this actually works, so with the for loop you are going through each step of the list which contents another list, is this a nested way to make the loop?

musical_groups = [
    ["Ad Rock", "MCA", "Mike D."],
    ["John Lennon", "Paul McCartney", "Ringo Starr", "George Harrison"],
    ["Salt", "Peppa", "Spinderella"],
    ["Rivers Cuomo", "Patrick Wilson", "Brian Bell", "Scott Shriner"],
    ["Chuck D.", "Flavor Flav", "Professor Griff", "Khari Winn", "DJ Lord"],
    ["Axl Rose", "Slash", "Duff McKagan", "Steven Adler"],
    ["Run", "DMC", "Jam Master Jay"],
]
# Your code here
for group in musical_groups:
    group = ", ".join(group)
    print(group)

1 Answer

Travis Alstrand
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Travis Alstrand
Treehouse Project Reviewer
Travis Alstrand
.a{fill-rule:evenodd;}techdegree seal-36
Travis Alstrand
Treehouse Project Reviewer

Hey Derek Graham Chema ! :wave:

Yes, so here we have a list of lists of strings.

So in our for group in musical_groups: loop, we're iterating over each list of strings.

We're then using the .join() method on each of those lists of strings which will take all of those strings inside and combine them into one long string, separated by the ", " that you provided.

So for example

["Ad Rock", "MCA", "Mike D."]

should turn into 

"Ad Rock, MCA, Mike D."