[Python] Type annotations for sqlalchemy model declaration

I can't figure how i could type annotate my sqlalchemy models code, what kind of type should i use for my model fields.

class Email(Model):
__tablename__ = 'emails'

name: Column[str] = Column(String, nullable=False)
sender: Column[str] = Column(
String, default=default_sender, nullable=False
)
subject: Column[str] = Column(String, nullable=False)
html: Column[str] = Column(String, nullable=False)
template_id: Column[UUID] = Column(
postgresql.UUID(as_uuid=True),
ForeignKey('templates.id'),
index=True,
)


Column type as well as Mapped satisfies the type linter of my editor, but it doesn't look like the right one as opposed to simple types like str/int/uuid

Should i use Optional[Column[str]] or Column[Optional[str]]?

What to use for relationship?

class Foo(Model):
...
bar: Bar = relationship(
'Bar',
order_by="desc(Bar.created_at)",
lazy='dynamic',
)


The result of accessing the relationship varies depending on the attribute lazy.

Continue reading...