[Python] Is there an elegant way to use a class attribute as a type annotation?

Using the same paradigm as in RDF, I'm modelling a class and its non-literal attributes as the id to the referenced object, like a URI in RDF.

For example:

GUID = NewType("GUID", int) # create a subclass of int

print(GUID.__name__) # prints 'GUID'

class Person:
id: GUID
parents: list["PersonId"]


When it comes to define PersonId, I have this piece of code:

def field_info(class_model: type, attr_name: str) -> tuple[type, str, Any]:
attributes = inspect.get_annotations(class_model)
assert attr_name in attributes
return (class_model, attr_name, attributes[attr_name])


PersonId = TypeAliasType("PersonId", Annotated[GUID, field_info(Person, "id")]) # create an alias of GUID.


and in the code, near the serialisation/deserialisation in the DB, I have checks like those to verify that the Annotation's type corresponds to the attribute's type.

(I took an example to simplify. The real code is agnostic from the Person class.)

assert Person.__name__ == "Person" # true
assert isinstance(PersonId, typing.TypeAliasType) # true
origin = get_origin(PersonId.__value__)
args = get_args(PersonId.__value__)
assert origin is Annotated # true
assert args[0] is GUID # true
assert args[1] == (Person, "id", GUID) # true
assert args[0] == args[1][2] # true


Is there be a way to directly define

PersonId = TypeAliasType("PersonId", Person.id) #AttributeError: type object 'Person' has no attribute 'id'

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