Loading collection data...
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.
It is also worth adding that if a key already exists in the form of a string, then we replace its value, and do not create a new key in the form of a symbol. It's not entirely clear from the description
Helpful comment, thanks.
Add this line at the end to be a bit more exhaustive:
Ruby strings are mutable. Did you mutated the input string?