Using uuid.UUID with PotgreSQL's UUID

I have a model using PostgreSQL’s UUID:

from sqlalchemy.dialects import postgresql

class MyModel(Base):
    __tablename__ = 'my-model'

    some_id = Column(postgresql.UUID(as_uuid=True), nullable=False)

SQLAlchemy lets me create instances as follows:

import uuid

a_uuid = uuid.uuid4()

MyModel(some_id=a_uuid)
MyModel(some_id=str(a_uuid))

However, the stubs here seem to only accept the latter, not the former:

error: Incompatible type for "some_id" of "MyModel" (got "UUID", expected "str")

Could support for the former be added?

(I tested with sqlalchemy-stubs master)

[ilevkivskyi]

@wbolster Looks like you answered your own question. I think you can also just use # type: ignore on the definition with the explicit annotation. Also I think your way can be simplified to:

if TYPE_CHECKING:
    PostgreSQLUUID = sqlalchemy.types.TypeEngine[uuid.UUID]
else:
    PostgreSQLUUID = sqlalchemy.dialects.postgresql.UUID(as_uuid=True)

[sirosen]

reveal_type is handy, but I mean that I don’t understand how sqlalchemy.types.TypeEngine[uuid.UUID] produces a Column[UUID*]. As far as I can tell, TypeEngine doesn’t even support subscripting. So is this some magic hint to sqlmypy?

(By the way, thanks for sharing the workaround!)