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Python Introducing Lists Build an Application Multidimensional Musical Groups

Multidimensional List, my code works if i copy and paste into VS code but the compiler on treehouse is throwing an error

i think i may just be thinking of this wrong, am i suppose to get them to all print on the same line? if so can you throw me a hint as to what method i shouldbe using?

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 groups in musical_groups:
    for x in groups:
        print(x + ", ")

1 Answer

Alex Koumparos
Alex Koumparos
Python Development Techdegree Student 36,862 Points

Hi Roger,

Your code prints every person on a separate line with a comma at the end of the line. The Challenge wants you to have a line for each group, and on each line it should list the members comma separated (but no comma at the end of the line). E.g, for the first group, it should like this:

Ad Rock, MCA, Mike D.

There is a built-in string method you can use, join().

Hope that helps


so i think i'm a bit closer but now the placement of mt comma is wrong, i think my brain has shut down...

for x in musical_groups:
    for y in x:
         listx += y.join(", ")