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How do you use dataclasses.field(compare=False) or field(repr=False) to exclude a specific field from the auto-generated __eq__ or __repr__? How do you implement custom ordering (<, <=, >, >=) for a dataclass using order=True, and what constraint does it place on field comparison? How do you convert a dataclass instance to and from a dictionary using dataclasses.asdict() and manual reconstruction? How would you implement inheritance between dataclasses, and what field-ordering rule must be respected across the hierarchy? How would you use dataclasses.replace() to create a modified copy of an immutable (frozen) dataclass instance? When would you choose a NamedTuple over a @dataclass, and vice versa, given their overlapping use cases? How would you use Python 3.10+'s kw_only=True (or per-field kw_only) to require dataclass fields be passed as keyword arguments only?
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How do you implement a custom __eq__ or __hash__ on a dataclass while still benefiting from its other auto-generated methods?

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Answer

Pass eq=False (or hash appropriately) to @dataclass to SKIP auto-generating that specific method, then define your OWN __eq__ or __hash__ method in the class body — the decorator only generates methods you haven't disabled, letting you selectively override just the behavior you need custom logic for.
@dataclass(eq=False)
class CaseInsensitiveString:
    value: str

    def __eq__(self, other):
        return isinstance(other, CaseInsensitiveString) and self.value.lower() == other.value.lower()
    def __hash__(self):
        return hash(self.value.lower())
Real-world example Implementing case-insensitive equality for a dataclass wrapping a string, where the default field-by-field comparison wouldn't be correct.

Common follow-ups: Why does defining a custom __eq__ on a regular (non-dataclass) class automatically set __hash__ to None unless you also define __hash__?

Magic Methods & Operator Overloading
All 15 Dataclasses & NamedTuples questions