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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by fionaj
fionaj
1,380 Points

I'm not sure how to print only the groups with 3 members.

groups.py 
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 item in musical_groups:
    if len(musical_groups) == 3:
        print(", ".join(item))

2 Answers

Rohald van Merode
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STAFF
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Rohald van Merode
Treehouse Staff
Rohald van Merode
.a{fill-rule:evenodd;}techdegree seal-36
Rohald van Merode
Treehouse Staff

Hey fionaj 👋

You're super close to the solution here! There's only one thing that stops your code from working and that is the conditional that you've created.

Currently, you're checking the length of the musical_groups list which is 7 (all nested lists in musical_groups) Instead you'll want to check the length of the item which represents a single group in your loop 🙂

for item in musical_groups:
    if len(item) == 3:
        print(", ".join(item))

Hope this helps!

Robbie Baker
Robbie Baker
3,700 Points
Robbie Baker
Robbie Baker
3,700 Points

The key here is just to remember items as objects inside the list. These can be other lists, strings, ints, etc.