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Python Introducing Lists Build an Application Multidimensional Musical Groups

Wayne Jackson
PLUS
Wayne Jackson
Courses Plus Student 866 Points
Posted by Wayne Jackson
Wayne Jackson
Courses Plus Student 866 Points

Unclear on how to List Members.

Hello All, a bit lost on this exercise. I've watched all the videos multiple times through and can't figure out how to combine the methods. Any hints would be helpful. Thanks

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 artist in musical_groups:
    artist = ", ".join(musical_groups)
    print(artist)

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The "musical_groups" list is the master list of lists. The one you want to join to get the members is "artist".

And you can print it out directly without the variable assignment if you want.

Wayne Jackson
Wayne Jackson
Courses Plus Student 866 Points
Wayne Jackson
Wayne Jackson
Courses Plus Student 866 Points

No matter how I try it I'm getting the: AttributeError: 'list' object has no attribute 'join' message. 

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 artist in musical_groups:  
    print(artist.join(musical_groups) + ", ")
Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Lists don't have a "join" method, strings do. Your "join" syntax was closer the first time, you just had the wrong argument.

What I was suggesting was instead of :point_right:   ", ".join(musical_groups)
...you might write this instead :point_right:   ", ".join(artist)