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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Min He
Min He
789 Points

group.py

for group in musical_groups: s = "," print(s.join(group))

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"],
]
s:
    s = ","
    print(s.join(group))for group in musical_group

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Hey Min He, your solution is very cleaver!

With some modifications, I was able to get your code to produce the expected correct output. I needed to create separate lines instead of a list of strings. 

s = ", "
print(s.join([", ".join(group) for group in musical_groups]))

Produces

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

However, including the corrections doesn’t pass because the checker doesn’t like the unexpected variable s and is looking for a regular for loop and not a list comprehension.

Can you figure out how to get the same output using a regular for loop with the variable s?

Post back if you need more help. Good luck!!!