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Python Introducing Lists Build an Application Multidimensional Musical Groups

Jordan Winka
Jordan Winka
3,884 Points
Posted by Jordan Winka
Jordan Winka
3,884 Points

Couldn't we just do a join and then print the string?

Wouldn't this work too?

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
members = ", ".join(musical_groups)
print (members)

2 Answers

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

That code is attempting to join all the groups into a single string, but the "join" method doesn't know how to handle a list containing other lists.

The challenge wants you to join the members of each individual group and print those out one at a time. That's where the loop comes in handy.

Now just as a preview, there is a way to do this with a one-liner using something called "list comprehension" which you will get to in later courses:

members = "\n".join([", ".join(g) for g in musical_groups])
print(members)

But this won't solve the challenge because it's specifically wanting you to use a loop.

jhon white
jhon white
20,006 Points
jhon white
jhon white
20,006 Points 
#first challenge :

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


#second challenge:

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

Good luck :))