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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Oscar Manuel Ruiz Reyes
Oscar Manuel Ruiz Reyes
4,176 Points

How can i make a string out of multidimensional music groups?

I completed the challenge joining the musical groups this way: 

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

But instead of joining all the groups in their indexes, for example, "Ad Rock", "MCA", "Mike D." on musical_groups[0] , i want to join every group in 1 string so every group will be in the same place,I'm not sure where to go from here, do I need to ,in some way ,do an extra step to join each individual line into a string or something?

If somebody could write the correct code with an explanation that would be much appreciated!

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 x in musical_groups:
    final=", ".join(x)
    #print(final)
print(", ".join(final))

1 Answer

Alexander Davison
Alexander Davison
65,469 Points
Alexander Davison
Alexander Davison
65,469 Points

:warning: Note that .join() is a method on a string that takes in a list, not the other way around. Confusing? I don't blame you. It's one of the strangest methods in Python.

For example...

my_list = ['a', 'b', 'c']
my_list.join(', ')  # Error!
', '.join(my_list)  # Correct

Try:

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