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saro lin
Courses Plus Student 531 Points.join() ?
what is the purpose of .join() ?
2 Answers
![Gregory Katchmar](https://uploads.teamtreehouse.com/production/profile-photos/2511562/micro_GNK_Avatar_2.jpg)
Gregory Katchmar
10,912 PointsCreates a string from a list. Given list['a', 'b', 'c'], the command ', '.join(list) will result in the string "a, b, c"
The command will only work on 100% string lists, so if an integer is in play, no go.
![Haider Ali](https://uploads.teamtreehouse.com/production/profile-photos/2869952/micro_pic.jpg)
Haider Ali
Python Development Techdegree Graduate 24,728 PointsHi Saro. As Chris said, `join()' is a method which is used on a string. It can be used to join things together into a string such as items in a list. E.g:
', '.join(['1', '2', '3'])
>>> '1, 2, 3'
Chris Freeman
Treehouse Moderator 68,425 PointsChris Freeman
Treehouse Moderator 68,425 PointsMoved to answer.
Chris Freeman
Treehouse Moderator 68,425 PointsChris Freeman
Treehouse Moderator 68,425 PointsExtending Gregory's answer, the
join()
is a string method (operates on the associated string). It says "I am a string. Use me as the glue to 'join' a container of string objects into one long string object".Many ask why isn't
join
alist
method since that is what is usually joined. As Gregory mentioned, if all of the items in the list to be joined are not cast as strings, then an error is raised. So it makes more sense as astr
method. Additionally, you can use a variety of containers as the argument tojoin
: