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Python Introducing Lists Build an Application Multidimensional Musical Groups

Jafar Arifdjanov
Jafar Arifdjanov
1,215 Points
Posted by Jafar Arifdjanov
Jafar Arifdjanov
1,215 Points

I don't understand what they want

I try this code it says it's wrong for item in musical_groups:

for thing in item:
    print(thing + ",")
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 item in musical_groups:

    for thing in item:
        print(thing + ",")

2 Answers

Jassim Alhatem
Jassim Alhatem
20,883 Points
Jassim Alhatem
Jassim Alhatem
20,883 Points

First task:

for lst in musical_groups:
    print((', ').join(lst))

You're looping through 'musical_groups' and getting the lists inside. Then you use .join() to create a string from each list. (aka iterable object). Read more about join()

Second task:

for lst in musical_groups:
    if len(lst) == 3:
        print((', ').join(lst))

You're looping through 'musical_groups' again and checking if the list contains 3 elements.

Hope this helps.

Phil Livermore
Phil Livermore
11,018 Points
Phil Livermore
Phil Livermore
11,018 Points

I think they want you to use str.join() and don't forget the space after the comma. str would be the separator, in this case the comma and space and the parameter for the join method would be each list from the first loop. You only need one for loop.