[Python] How to make dataclass instance attribute non-public and an __init__ arg?

If I want an instance attribute to be:

• Non-public (aka have a single leading underscore)
• Be a parameter in the __init__ signature

Normally, I would do this:

class Foo:
def __init__(self, bar: str):
self._bar = bar

foo = Foo(bar="bar") # foo.bar would raise an AttributeError


However, in dataclasses, I'm unsure how to do this.

from dataclasses import dataclass

@dataclass
class Foo:
bar: str # This leaves bar as a public instance attribute


What is the correct way to do this in dataclasses.dataclass?

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