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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Ethan Pyles
Ethan Pyles
2,710 Points

I am getting an AssertionError. I feel that I might not completely understand what the assumptions are for the output.

I enjoy music groups and their members possibly more than anyone that I know. The arrangement in this table where each row is a group and the group name is contained in column one seems logical. I begin to find familiarity in the table but John Lennon as a group name?

I faintly think that I understand properly, but please help me out.

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
members=[]
for group in musical_groups:
    print("Group Name: ",group[0])
    print(group[0], "Members:")
    members=", ".join(group[1:])
    print(members)

2 Answers

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

The AssertionError is coming from the checker. These assertions mean a test comparison failed. Look deeper into the comparison to see where the error may be.

You seem to be over complicating the task.

  • the join should be over all members of the group. The first item isn’t the group name.
  • you can remove the first two print statements withIn the function definition

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

Ethan Pyles
Ethan Pyles
2,710 Points
Ethan Pyles
Ethan Pyles
2,710 Points

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

members=[] for group in musical_groups members=", ".join(group[0:]) print(members)