`vector_store.create_collection()` fails: `AttributeError: 'NoneType' object has no attribute 'get_or_create'`

[amotl]

Problem

    def create_collection(self) -> None:
        if self.pre_delete_collection:
            self.delete_collection()
        with self._make_sync_session() as session:
>           self.CollectionStore.get_or_create(
                session, self.collection_name, cmetadata=self.collection_metadata
            )
E           AttributeError: 'NoneType' object has no attribute 'get_or_create'

.venv/lib/python3.12/site-packages/langchain_postgres/vectorstores.py:542: AttributeError

[amotl]

After helping with vector_store._init_models_with_dimensionality(3), it fails when invoking vector_store.create_collection().

E               sqlalchemy.exc.ProgrammingError: (crate.client.exceptions.ProgrammingError) RelationUnknown[Relation 'langchain_collection' unknown]
E               [SQL: SELECT langchain_collection.uuid AS langchain_collection_uuid, langchain_collection.name AS langchain_collection_name, langchain_collection.cmetadata AS langchain_collection_cmetadata
E               FROM langchain_collection
E               WHERE langchain_collection.name = ?
E                LIMIT ?]
E               [parameters: ('test_collection', 1)]
E               (Background on this error at: https://sqlalche.me/e/20/f405)

.venv/lib/python3.12/site-packages/crate/client/http.py:238: ProgrammingError