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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Samir Poonawala
Samir Poonawala
29,951 Points

Difficulty with final challenge of Introducing Lists course

Tried following the same structure as what we did for expenses.py file a few videos back but can't seem to get the code running. I get an "Attribute Error: 'int' object has no attribute 'join'"

Thanks in advance for your 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
musical_group = musical_groups[0]
for musical_group in musical_groups:
    print(musical_group.join(", "))
    musical_group+= 1

2 Answers

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher
Craig Dennis
Craig Dennis
Treehouse Teacher

Remember, the join method is off of the string. musical_group there is a list of members.

Let me know if that hint doesn't do the trick. Looking good!

Mustafa BaลŸaran
Mustafa BaลŸaran
28,046 Points
Mustafa BaลŸaran
Mustafa BaลŸaran
28,046 Points

Please think how you can use join() method with the predefined separator and the loop.

# define the separator
sep = ", "
#create an empty string to use in output
band_string = ""
#iterate over each musical group
for band in musical_groups:  
    #join separator on each musical group
    # ....
    #print the output
    print(band_string)

for a short overview of join() method, please see https://www.tutorialspoint.com/python/string_join.htm

Jake Kobs
Jake Kobs
9,215 Points
Jake Kobs
Jake Kobs
9,215 Points

Thank you Mustafa! This managed to help me!