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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Darrin Spell Jr
.a{fill-rule:evenodd;}techdegree
Darrin Spell Jr
Full Stack JavaScript Techdegree Student 10,303 Points

Im on task 2

I have no clue how to approach it. Please help.

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"],
]
for group in musical_groups:
    print(", ".join(group))

1 Answer

Cameron Nilon
Cameron Nilon
15,601 Points
Cameron Nilon
Cameron Nilon
15,601 Points

Hey Darrin,

let's work this out. So for the second task, you need to check if the musical group is a trio i.e three members. So in Python terms, the list has three items.

So you can still use your join but wrap it in an if statement that checks whether the list has three.

If you still don't get it or I didn't make much sense, here is what you could do.

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"],
]

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

Hope this helps.