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How can I properly type-hint methods in different files that would lead to circular imports?

I am writing a Python package where I have two classes in different files that (indirectly) depend on each other.
If I wouldn't care about type-hints, there would be no problem, but unfortunately, I do like static type-hinting.
Therefore, I need one class for typing the methods of the other and vice versa.
Of course, this leads to a circular import, but using [forward references](https://peps.python.org/pep-0484/#forward-references), I managed to arrive at the following code:

```python
# process.py

from helpers import Helper

class Process:

    def do_something(self, helper: Helper):
        ...
```

```python
# helpers.py

class Helper:
    
    def update(self, process: "Process"):
        ...
```

This code runs without problems, but when running `mypy`, it complains that `Name "Process" is not defined`.
I know I could [silence these errors](https://mypy.readthedocs.io/en/stable/common_issues.html#spurious-errors-and-locally-silencing-the-checker), but I was wondering whether there is a "proper" way to fix the type-hinting in this case.