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Python Introducing Lists Build an Application Multidimensional Musical Groups

james mchugh
james mchugh
6,234 Points

It say .join is invalid syntax

If I remove the .join I get a message that I need to use the .join method to join the members together. I've tried a few different ways of using .join and can't seem to get it. I'm looking at code from previous projects, but I'm not getting it.

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"],
group = .join(musical_groups)
for members in musical_groups:
    print(", " + musical_groups)

1 Answer

Eric M
Eric M
11,545 Points

Hi James,

I think the syntax for the String join method- [String].join([iterable]) - was covered in an earlier video but I will admit that I don't find it intuative.

The seperator, in this case a comma, can be entered as a string literal and then the join method called on that string literal with the items to join (in this case our band members) as arguments.

As we want to do this band by band in this challenge, you'll need to put the join method within your loop.


for members in musical_groups:
    print(", ".join(members))
james mchugh
james mchugh
6,234 Points

Thanks Eric, I was almost there at one point, except I was joining musical groups and I added a line that didn't need to be there. Thanks for your help. Best answer.