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.
I understand now. Thank you for the explaintion.
Read the description. It states
If array is empty, null or None, or if only 1 Element exists, return 0., meaning that thearrayvariable may be null and you will have to deal with null values.You are recieving an error because a null value can't be sorted since it's not iterable.
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