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Python Introducing Lists Build an Application Multidimensional Musical Groups

Pradeep Arumugam
Pradeep Arumugam
665 Points
Posted by Pradeep Arumugam
Pradeep Arumugam
665 Points

syntax error

I am trying to finish this part with the .join method, but it does not work for me. Why is that?

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
music_group = 1
for music in musical_groups:
    print("* music group #{}".join(music_group, sum(music group)))
    music_group += 1

1 Answer

Richard Li
Richard Li
9,751 Points
Richard Li
Richard Li
9,751 Points

str.join(iter) method takes only one iterable, but here you passed in two(mucis_group, sum(music group))

Also the return of str.join(target) is that it will concatenate each member of the target, joining them with str for example:

demo = ['a', 'b', 'c', 'd'] 
#ps.: all must be string, doesn't work on any number)

"@".join(demo)

the return value will be "a@b@c@d@"

take this into consideration and try revising your code~!

Hope this helps!