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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Spacey Bread
Spacey Bread
6,256 Points

I can't understand this error

Can somebody help me fix this code? I don't understand what is wrong with it

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:
    print(", ".join(musical_groups(x)))
    x = x + 1

1 Answer

diogorferreira
diogorferreira
19,363 Points
diogorferreira
diogorferreira
19,363 Points

Hi, when you are looping through the musical_groups x will be set to each individual list inside that list so in the first iteration it would equal to: ["Ad Rock", "MCA", "Mike D."] and so on...

  • The for loop wouldn't need to increment by 1 to move into the next iteration - it does it by itself, and that would result in an error because you're trying to do x = ["Ad Rock", "MCA", "Mike D."] + 1 A list cannot be concatenated to an integer
  • Last thing, you can't call musical_groups(x) in .join() its a list not a function, to solve this you can just pass in x to join()

Here's how your code could look:

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