Odd: "Expected type '() -> None', got '() -> None' instead"

Pycharm 2021.1 community edition shows that very weird message:

"Expected type '() -> None', got '() -> None' instead"

I stared at this for 10 minutes to find the difference between expected and received types, without success.

This happens for the following code (minimal example):

```python

class T1:
    def f1(self):
        f = self.__init__

```

I am rather confused now.