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Hi,
According to https://peps.python.org/pep-0544/#explicitly-declaring-implementation it should be possible to explicitly inherit from Protocols. This however breaks the dataclass constructor when using the @property decorator in the protocol, see this example:
```python
from typing import Protocol
from dataclasses import dataclass
class SomeProtocol(Protocol):
 @property
 def some_value(self) -> str: ...
@dataclass
class SomeDataclasss(SomeProtocol):
 some_value: str
if __name__ == '__main__':
 a = SomeDataclasss(some_value="value") # this crashes with AttributeError: can't set attribute 'some_value'
```
The pattern of @property in the protocol is one taken from the mypy docs (see https://mypy.readthedocs.io/en/stable/protocols.html#recursive-protocols for example). 
When removing the explicit inheritiance mypy also correctly typechecks the dataclass implementation when doing something like, only the explicit inheritance seems to fail in python
```python
a: SomeProtocol = SomeDataclass()
```

Here's the error without dataclasses:
------
from typing import Protocol
class SomeProtocol(Protocol):
 @property
 def some_value(self) -> str: ...
class SomeClass(SomeProtocol):
 def __init__(self, some_value):
 self.some_value = some_value
if __name__ == '__main__':
 a = SomeClass(some_value="value")
------
Traceback (most recent call last):
 File "foo.py", line 12, in <module>
 a = SomeClass(some_value="value")
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 File "foo.py", line 9, in __init__
 self.some_value = some_value
 ^^^^^^^^^^^^^^^
AttributeError: property 'some_value' of 'SomeClass' object has no setter
And here it is without Protocol:
--------
class SomeProperty:
 @property
 def some_value(self) -> str: ...
class SomeClass(SomeProperty):
 def __init__(self, some_value):
 self.some_value = some_value
if __name__ == '__main__':
 a = SomeClass(some_value="value")
--------
Traceback (most recent call last):
 File "foo.py", line 10, in <module>
 a = SomeClass(some_value="value")
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 File "foo.py", line 7, in __init__
 self.some_value = some_value
 ^^^^^^^^^^^^^^^
AttributeError: property 'some_value' of 'SomeClass' object has no setter

So is the conclusion that this should be closed as "not a bug"?

I think the behavior with regular classes is expected (that's just how inheritance works), but a case could be made that dataclasses should handle this case specially.

What would dataclasses do that's different from a regular class?