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Python Introducing Lists Build an Application Multidimensional Musical Groups

Brent Capuano
Brent Capuano
949 Points
Posted by Brent Capuano
Brent Capuano
949 Points

Need help on this quiz

Here is a multi-dimensional list of musical groups. The first dimension is group, the second is group 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"],
]

line_number = 1
members = ", ".join(musical_group)
for group in musical_groups:
    print("Group #{}:" + members.format(line_number)) 
    line_number += 1

1 Answer

Øyvind Andreassen
Øyvind Andreassen
16,840 Points
Øyvind Andreassen
Øyvind Andreassen
16,840 Points

Hey Brent Capuano,

I think you need to re-read the task. But you are actually pretty close, but let's break it down.

line_number = 1
members = ", ".join(musical_group)
for group in musical_groups:
    print("Group #{}:" + members.format(line_number)) 
    line_number += 1

It doesn't care about the position the band has in the list so you can get rid of the line_number. You are also declaring members by joining musical_group, the problem is that this variable doesn't exist. But the solution is on that line.

If we move declaring members to inside the for-loop, and print members you'll pass the challenge.

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

To make this code even more concise you could also just print the join function.