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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Quinten Rowland
Quinten Rowland
1,310 Points

In a multi dimensional list, how do I loop through each list and separate the objects with a comma?

I'm not certain that this is the right phrasing... it's the exercise at the very end of the beginning lists course taught by Craig Dennis. Thanks a lot!

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 musical_group in musical_groups
    print("{}".format(musical_groups))
musical_group.join(", ")

2 Answers

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

You have the right idea to use "join", but:

  • the "for" line should end with a colon
  • the join syntax is "backwards", call the method on the string and pass the list as the argument
  • the joined list will be the thing you want to "print" in the loop
Quinten Rowland
Quinten Rowland
1,310 Points

no matter what I try it keeps saying there are two problems with my code. I just don't understand what i'm doing wrong, and how every single time i'm two steps away from being correct :((

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

What I was suggesting was fixing the syntax issues and then putting the "join" expression in the "print":

for musical_group in musical_groups:
    print(", ".join(musical_group))
Quinten Rowland
Quinten Rowland
1,310 Points
Quinten Rowland
Quinten Rowland
1,310 Points

This comes up as incorrect and says that there are two problems with my code. When i rearrange it from this position into something that I think would work it usuallyyy says that there are two problems with my code, unless it says it's just invalid syntax.

variable = ", ".join(musical_groups) for musical_group in musical_groups: print({} , variable.format(musical_groups))

thank you for your help!