It unfortunately leaves you with a choice of either taking advantage of dynamic annotations or using MyPy, but not both.

And as the sibling comment says, typescript did it so much better.

    ```py
    from typing import TYPE_CHECKING

    if TYPE_CHECKING:
        Foo = "expression that mypy can understand"
    else:
        Foo = "dynamic expression"
    ```

    class Book(MonDoc):
        title = StrField()
        yearPublished = IntField()

1: https://github.com/cabalamat/frambozenapp

  class Book(MonDoc):
    title: str = StrField()
    yearPublished: int = IntField()

  def IntField() -> int:
    ...

When I define something as a `StrField` I'm already saying it's a string, so I shouldn't have to say it again elsewhere. It would be nice if Python has an API such that I can write code within my `StrField` class that tells python that `title` is a `str`, but to the best of my understanding this doesn't exist.

Could you explain what you mean by this? I'm not clear on what typescript behavior this describes.

https://www.typescriptlang.org/docs/handbook/utility-types.h...