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Python Introducing Lists Build an Application Multidimensional Musical Groups

Balazs Ferencz
Balazs Ferencz
4,993 Points
Posted by Balazs Ferencz
Balazs Ferencz
4,993 Points

Why is this not working as intended please?

Was meant to only print out the trios in this challenge, separated with a comma and space.

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"], ]

for members in musical_groups: members = ", ".join(members) if len(members) == 3: print(", " + members)

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"],
]

for members in musical_groups:
    members = ", ".join(members)
    if len(members) == 3:
        print(members)

1 Answer

Zimri Leijen
Zimri Leijen
11,835 Points

You're joining it before checking the length, which affects the length.

check the length first, then join.

Balazs Ferencz
Balazs Ferencz
4,993 Points
Balazs Ferencz
Balazs Ferencz
4,993 Points

Thanks :) I figured it out by the time your answer came :) But still nice one, thanks again. :)