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What does the @dataclass decorator automatically generate for a class? How do you create a simple immutable record using collections.namedtuple? Why can't you use a mutable default value (like an empty list) directly as a dataclass field default, and how do you use field(default_factory=...) to fix it? How do you make a dataclass immutable (read-only after creation) using frozen=True? How does typing.NamedTuple differ from collections.namedtuple in terms of syntax and type annotation support? How do you add validation logic to a dataclass field using __post_init__? 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?
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How do you specify default values for dataclass fields, and what ordering restriction applies?

Intermediate

Answer

Assign a default value directly after the type annotation, exactly like a regular function parameter default — and just like function parameters, any field WITH a default must come AFTER all fields WITHOUT one, or Python raises a TypeError at class definition time.
@dataclass
class User:
    name: str          # required, no default
    role: str = "user"  # has a default, must come after required fields

u = User("Sam")
print(u.role)  # 'user'
Real-world example Defining sensible default values for optional configuration fields on a dataclass, like a default role or status.

Common follow-ups: What error occurs if you try to declare a field WITHOUT a default AFTER one that HAS a default?

Exception Handling
All 15 Dataclasses & NamedTuples questions