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Python Introducing Lists Build an Application Multidimensional Musical Groups

Posted by Brendan Dzeguze
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Dzeguze
Front End Web Development Techdegree Graduate 14,567 Points

i need help with python code.

how do i only print trios? i keep getting error: type object 'int' has no attribute 'toline'.

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
for musical_group in musical_groups:
    toline = ", ".join(musical_group)
    if int.toline <= 3:
        print(toline)

2 Answers

Alexander Cordes
PLUS
Alexander Cordes
Courses Plus Student 12,628 Points
Alexander Cordes
Alexander Cordes
Courses Plus Student 12,628 Points

In your code you are converting the list into a string before you are trying to count the number of strings in that list. Therefore your if function will count the number of characters in each list (or now string) instead of the number of musicians.

Use the if function first to count the number of strings (musicians) in each list: In your case that would be len(musical_group) and if they are == 3 then convert into a string and print.

use == because otherwise it would print duos if there were any

jb30
jb30
44,807 Points
jb30
jb30
44,807 Points

If you want to find the length of the string contained in the variable toline, you can use len(toline), which will give you the number of characters in the string. If you want to find the length of the array musical_group, you can use len(musical_group), which will give you the number of strings in the array.