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Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.
Get started now by creating a new collection.
This does not fulfill the requirements at all.
Definitely not best practice. This fails to check if the correct amount of numbers are in each place, and I see what they were trying to do with the optional area code, but if you entered a phone number without an area code, it would fail, too, as you need a space before the phone number in that case.
ok
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