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Python 3.10 is now available in preview.


Normalizes and type checks that the given argument is a valid key or keys.

A wrapper around NormalizeAndTypeCheck() that accepts strings, Keys, and Entities, and normalizes to Keys.

keys a Key or sequence of Keys

A (list of Keys, bool) tuple. See NormalizeAndTypeCheck.

BadArgumentError arg is not an instance or sequence of one of the given types.