[issue39134] can't construct dataclass as ABC (or runtime check as data protocol)

[Alexander Hirner]

Alexander Hirner <a.hirner at gmail.com> added the comment:

Dropping ABCMeta stops at instantiation. This should be in the dataclass code that's been generated.

  File "<string>", line 2, in __init__
AttributeError: can't set attribute


Repro:
```
class QuasiABC:
    @property
    @abstractmethod
    def x(self) -> int: ...

@dataclass(frozen=True)
class E(QuasiABC):
    x: int

E(10)
```

Interestingly, frozen=False is giving the same error.

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue39134>
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