refactor(collection): make TDoc typevar covariant in collection classes

Author: tharropoulos

src/typesense/collection.py

@@ -35,7 +35,7 @@
 from typesense.synonyms import Synonyms
 from typesense.types.document import DocumentSchema
 
-TDoc = typing.TypeVar("TDoc", bound=DocumentSchema)
+TDoc = typing.TypeVar("TDoc", bound=DocumentSchema, covariant=True)
 
 
 class Collection(typing.Generic[TDoc]):

src/typesense/collections.py

@@ -28,7 +28,7 @@
 from typesense.types.collection import CollectionCreateSchema, CollectionSchema
 from typesense.types.document import DocumentSchema
 
-TDoc = typing.TypeVar("TDoc", bound=DocumentSchema)
+TDoc = typing.TypeVar("TDoc", bound=DocumentSchema, covariant=True)
 
 
 class Collections(typing.Generic[TDoc]):