Invalid base class when using pydantic_model_creator

[angel-langdon]

Describe the bug When I have a tortoise.models.Model and then convert it to a PydanticModel using the pydantic_model_creator function. It raises a mypy error because it says that created class is not a valid base class

To Reproduce

from typing import Type
from uuid import UUID, uuid4

from pydantic.fields import Field
from tortoise import fields, models
from tortoise.contrib.pydantic import pydantic_model_creator
from tortoise.contrib.pydantic.base import PydanticModel


class ProjectModel(models.Model):
    id = fields.UUIDField(  # noqa: A003, VNE003
        pk=True, default=uuid4, description="Resource indentifier."
    )
    name = fields.CharField(
        max_length=255, descirption="Project verbose name."
    )
    created = fields.DatetimeField(
        auto_now_add=True, description="Timestamp resource has been created."
    )
    updated = fields.DatetimeField(
        auto_now=True, description="Timestamp resource has been updated."
    )

    class Meta:
        table = "projects"


ProjectPydantic: Type[PydanticModel] = pydantic_model_creator(
    ProjectModel, name="Project"
)


class Project(ProjectPydantic): # raises the error
    creator_id: UUID = Field(description="Project creator and owner.")

Expected behavior The created class ProjectPydantic should be a valid base class.

[tiwilliam]

Try hinting using ProjectPydantic = pydantic_model_creator(ProjectModel, name="Project") # type: PydanticModel instead. Not optimal but this works for me. Dynamic base classes in mypy are discussed here: https://github.com/python/mypy/issues/2477

[Kulikovpavel]

Sorry, could you explain how to work with that and with mypy? Hinting it that way isn't working

This example produces errors in mypy https://tortoise-orm.readthedocs.io/en/latest/examples/fastapi.html

app/main.py:20: note: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases
app/main.py:26: error: Variable "app.models.UserIn_Pydantic" is not valid as a type
app/main.py:26: note: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases
app/main.py:27: error: UserIn_Pydantic? has no attribute "dict"
app/main.py:45: error: Variable "app.models.UserIn_Pydantic" is not valid as a type
app/main.py:45: note: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases
app/main.py:46: error: UserIn_Pydantic? has no attribute "dict"

[jvaesteves]

I had the same problem, and only using TypeAlias and silencing mypy I was able to circumvent this issue and properly have code completion on VSCode.

from typing import TypeAlias
ProjectPydantic: TypeAlias = pydantic_model_creator(ProjectModel, name="Project")   # type: ignore[misc]