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Python Introducing Lists Build an Application Multidimensional Musical Groups

Alon Rozmarin
PLUS
Alon Rozmarin
Courses Plus Student 2,083 Points

Hi someone can help me?

I got it!

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:
    if len(musical_groups) == 3:
        print(", ".join(group))
    else:
         continue

2 Answers

Szymon Dabrowski
Szymon Dabrowski
2,161 Points

The reason why I used group instead of musical_groups is because musical_groups is a name that contains the multi-dimensional list and not actually defining either of the dimensions if that makes any sense.

The first dimension is group and the second is group members. So ["Ad Rock", "MCA", "Mike D."] all together would be considered a group and, "Ad Rock", "MCA", "Mike D." separately group members.

So the second part of the challenge asks us to only display groups that have 3 members in them. So we can straight away tell that we need to use the first dimension which is the group. You got the len() function correctly to calculate how many members there are but selected the incorrect dimension in the list. and, you have also correctly compared all the groups to be equal (==) to the number 3 which stands for 3 names in a group. So the only thing you have missing is the correct dimension to look through which is group.

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

I hope this makes more sense for you as I was stuck on this part for a while myself.

In the line if len(musical_groups[0]) == 3:, the value of musical_groups[0] does not change when the value of group changes. Try comparing the length of the group array instead.