[issue39442] from __future__ import annotations makes dataclasses.Field.type a string, not type

[Marco Barisione]

Marco Barisione <marco at barisione.org> added the comment:

This is particularly annoying if you are using `Annotated` with a dataclass.

For instance:
```
from __future__ import annotations

import dataclasses
from typing import Annotated, get_type_hints


@dataclasses.dataclass
class C:
    v: Annotated[int, "foo"]


v_type = dataclasses.fields(C)[0].type
print(repr(v_type))  # "Annotated[int, 'foo']"
print(repr(get_type_hints(C)["v"]))  # <class 'int'>
print(repr(eval(v_type)))  # typing.Annotated[int, 'foo']
```

In the code above it looks like the only way to get the `Annotated` so you get get its args is using `eval`. The problem is that, in non-trivial, examples, `eval` would not be simple to use as you need to consider globals and locals, see https://peps.python.org/pep-0563/#resolving-type-hints-at-runtime.

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nosy: +barisione

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<https://bugs.python.org/issue39442>
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