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Python Introducing Lists Build an Application Multidimensional Musical Groups

Brent Capuano
Brent Capuano
949 Points
Posted by Brent Capuano
Brent Capuano
949 Points

Help with Introducing List Final Quiz

I need help with this quiz

cal_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"], ]

My Code

line_number = 1 members = ", ".join(musical_group) for group in musical_groups: print("Group #{}:" + members.format(line_number)) line_number += 1

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"],
]

line_number = 1
members = ", ".join(musical_group)
for group in musical_groups:
    print("Group #{}:" + members.format(line_number)) 
    line_number += 1

1 Answer

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,716 Points
Jeff Muday
Jeff Muday
Treehouse Moderator 28,716 Points

Parts of your code work-- let's build on that.

The Python join is a little odd compared to its JavaScript counterpart. The join() is a string method which "glues" a list together with the string in between each member.

this_group = ["Harry","Ron","Hermione"]
this_string = "-".join(this_group)
print(this_string)

Will output this:

Harry-Ron-Hermione

You got the correct concept of looping through the musical_groups. Good job there. You also understood we could put members together with the "join" statement.

The "for" loop iterates through musical_groups. So on each iteration of the loop the variable group is instantiated with a list containing the members of one of the groups.

so... you can replace the body of the for loop with your idea about members = ", ".join(group)

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

Good luck on your Python adventure!