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Python Python Collections (2016, retired 2019) Slices Deleting Or Replacing Slices


I don't understand this, it confused me so much

2 Answers

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Breaking it down:

# the last 6 elements of the list rainbow
# "".join() creates a string using these elements. 
# "" means the separation between elements is the empty string, that is, no space
# wrapping the expression in [ ] creates a list with the joined string as the only item

Creating a string from a list of items can seem confusing. A built-in method on strings is the .join(some_list) method. It says "use this string as a connecting segment to create a new string using each of the items in some_list"

An example:

>>> a = ['1', '2', '3', '4', '5', '6']
>>> "---".join(a)
>>> "-".join(a)
>>> "".join(a)

Post back if you have any more questions. Good luck!!

Thanks so much, I didn't realise what u needed to join with came before .join, well now I understand this but a lot of the stuff in my stage is actually really confusing me, but I don't want to start the course all the way from the beginning, I don't know what to do

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Sometimes repeating content can help to reinforce what you know and help learn the concepts that need a better understanding. Feel free to post more questions to the community forum if you get stuck again.

I guess its the quotation marks that really throw me

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Answer expanded above to include more .join() examples.