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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by mm78
mm78
5,190 Points

Introducing Lists - Challenge Task 2 of 2

Hello -

Although I can print the number of members within musical_groups I'm unable to return groups with three members.

My original thought was creating a function that populates an empty list using the append method, but thus far my function is inoperable.

Any help is greatly appreciated.

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 group in musical_groups:
    members = ", ".join(group)
    print(members)
    print(len(group))

3 Answers

Blake Kazmierzak
Blake Kazmierzak
2,491 Points

From what I understand, you are trying to return groups that only have exactly 3 members. So, inside your for loop, you should include an 'if' condition that restricts the results to items containing only 3 members.

Example: 

for group in musical_groups:
    if len(group) == 3: # checks to see if the length of the group is equal to 3 members
        print(group) # prints only those items that have a length of 3
Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

You won't need to "print" the size of the group. But you'll need to test it to see if the group has three members, and print the group members (or not) based on that test.

An "if" statement would be good for this.

mm78
mm78
5,190 Points
mm78
mm78
5,190 Points

Thank you!

Script is working perfectly now.

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

mm78 — Glad to help. You can mark a question solved by choosing a "best answer".
And happy coding!