code: def test_conversion_once(a_post_init, b_post_init, c_post_init):
      def converter(x):
          nonlocal called
          assert not called
          called = True
          return x
  
      class A(eqx.Module):
          x: int = eqx.field(converter=converter)
  
          if a_post_init:
  
              def __post_init__(self):
                  pass
  
      class B(A):
          if b_post_init:
  
              def __post_init__(self):
                  pass
  
      class C(B):
          if c_post_init:
  
              def __post_init__(self):
                  pass
  
      called = False
      A(1)
      assert called
  
      called = False
      B(1)
      assert called
  
      called = False
      C(1)
      assert called
  
imports: import abc
  import dataclasses
  import functools
  import inspect
  from collections.abc import Callable
  from dataclasses import InitVar
  from typing import Any, Optional
  import equinox
  import equinox.internal
  import jax
  import jax.numpy
  import jax.tree_util
  import pytest
  from .helpers import tree_allclose
label_desc: Use image node_id 38 for calling a global function with example usage: test_conversion_once(a_post_init, b_post_init, c_post_init) and returns: x