Python Introducing Lists Build an Application Multidimensional Musical Groups

Thomas Wilhelm
Thomas Wilhelm
3,714 Points

Need help on Step 1 of Multidimensional Musical Groups!

I'm getting the error of it expecting a str object but hitting a list object. I'm not sure how to get it converted to a string. Would someone be able to walk me through the process? I think I found the answer, but I don't recall going over it, nor do I understand it. The goal of it is to print every list within this musical_groups list separated by ", ".

Thank you!

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 group in musical_groups:
    band = ", ".join(musical_groups)
    print(band)
Filipe Martins
Filipe Martins
2,824 Points

What are you expecting as output ? all names separated by "," ?

Thomas Wilhelm
Thomas Wilhelm
3,714 Points

Right, sorry. So you are supposed to print out each individual list, separated by ", "

2 Answers

Steven Parker
Steven Parker
200,760 Points

You're close, but it's not the entire "musical_groups" array that you want to join and print, but each individual "group". :wink:

    band = ", ".join(group)
Thomas Wilhelm
Thomas Wilhelm
3,714 Points

OK. So after pondering it over the course of the day (or really just stepping away for work then trying it again, I settled on this:

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
a = 0
for group in musical_groups:
    band = ", ".join(musical_groups[a])
    print(band)
    a += 1

Which worked! So...moving on. Thank you!

Steven Parker
Steven Parker
200,760 Points

That works, but the loop has already isolated the specific "group" for you so you can do it a bit more simply and without the need for the separate indexing variable ("a").

See the example I added to my answer.