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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by William Wagar
William Wagar
1,436 Points

Can't get the code right for this join

I keep getting errors when I try and join the items in each list together. Please help.

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:
    print(group.join(", "))
Aaron Jorgensen
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Aaron Jorgensen
Python Development Techdegree Graduate 13,658 Points
Aaron Jorgensen
.a{fill-rule:evenodd;}techdegree seal-36
Aaron Jorgensen
Python Development Techdegree Graduate 13,658 Points

Hello William, You are just missing a step. by using .join on group you, Python is trying to find an attribute 'join' for the list 'group'.. The code below demonstrates the join on the separator and the group as the passed in argument.

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:
    print(", ".join(group))