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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Caroline Louw
Caroline Louw
12,155 Points

what is wrong with my code? How do I add the group members together using the join method?in python

It says that join is not an attribute on list object

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:
    for group[0] in musical_groups:
        group.join(", ")
        print(group)

2 Answers

Christian Beckett
Christian Beckett
11,123 Points

Well Caroline Louw Your code should look like this Hope it helps.

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"],
]
for group in musical_groups: # loop through the list of lists
        print('. '.join(group) + "\n") # print each member joined by a seperator
Caroline Louw
Caroline Louw
12,155 Points

Hi Christian Beckett. It's says AssertionError and it is not getting the code it expected.

Christian Beckett
Christian Beckett
11,123 Points

Alright Caroline Louw I edited it. it should work how you desire now. Actually, Im just going to post what i had for the whole challenge.

Christian Beckett
Christian Beckett
11,123 Points

and for second task should be something like this 

for group in musical_groups: # loop through the list of lists
        if len(group) == 3: #only print out the groups with 3 members
            print('. '.join(group) + "\n") # print each member joined by a seperator
Caroline Louw
Caroline Louw
12,155 Points

Thank you

Christian Beckett
Christian Beckett
11,123 Points

no problem sorry its a learning experience for all of us. advanced pythons got me over here putting code that shouldn't go where it is XD

Boris Sem
Boris Sem
1,608 Points
Boris Sem
Boris Sem
1,608 Points

I believe the whitespace goes before. As in : ", ".join(group)