How to refer to nested Python dataclasses? [duplicate]

Notes On Similar Q&As:

• This question is not addressed in Nested Python class needs to access variable in enclosing class, which is dealing with relationships between a "parent" and nested "child" class, and does not address @dataclasses.dataclass classes.
• This question is addressed in Python - reference inner class from other inner class. I thought the code from the accepted answer there was working, but a double-check after a comment below shows it is not, when using normal classes.

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I'm trying to do a simple nesting of multiple Python @dataclass decorated classes within another class, and have later classes refer back to the earlier ones. If I do not nest them at all, they work as expected, being able to include the first class defined into an object in the second class:

from dataclasses import dataclass, field

@dataclass
class A:
  z:int = field(default=0)

@dataclass
class B:
  a:A = field(default=A(z=1)) ### Object that is class A is included in class B

b = B(a=A(z=3))
print(f'b = B(a=A(z=3)); b.a.z={b.a.z}; b={b}')

But if I try to do the same inside of another class (in this case, not a dataclass), the "B" class cannot see the "A" class. In the below code, the definition of a as a type of A fails with a NameError: "name A is not defined". I've tried A and C.A, neither work.

Note that the other functions in the C class are able to see both A and B just fine, just inside dataclass B cannot see dataclass A.

class C:
  @dataclass
  class A:
    z:int = field(default=0)

  @dataclass
  class B:
    a:A = field(default=A(z=1)) ### NameError: name 'A' is not defined

  def __init__(self):
    self.b = C.B(a=C.A(z=3))

  def print_info(self):
    print(f'b = C.B(a=C.A(z=3)); b.a.z={self.b.a.z}; b={b}')

c = C()
c.print_info()

However, if I convert these to normal Python classes, it works in the nested case:

Rechecking, it turns out this is broken in normal classes as well (per comment below).

Strangely, if one nests dataclass A inside dataclass B, with B still inside class C, it does work - B has direct access to A, but nothing else in class C has direct access to A.

Question

Is it possible to define nested dataclasses with having the later ones access the earlier ones at the same level? If so, how?

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