Curious: seemingly useless OSDK python function

Saw this in a Python OSDK recently and it’s in all my object types.

Confusing with both self.primary_key() and self.get_primary_key() which begs the question, what exactly is the former for? I can’t really fathom a use case here so curious as to why?

The primary_key()method is used to get the API name of the primary key property, as a helper to know which property that is on your object type

How come it needs to be publicly exposed?