code: def test_identity(getkey):
      identity1 = eqx.nn.Identity()
      identity2 = eqx.nn.Identity(1)
      identity3 = eqx.nn.Identity(2, hi=True)
      identity4 = eqx.nn.Identity(eqx.nn.Identity())
      assert identity1 == identity2
      assert identity1 == identity3
      assert identity1 == identity4
      x = jrandom.normal(getkey(), (3, 5, 9))
      assert jnp.all(x == identity1(x))
      assert jnp.all(x == identity2(x))
      assert jnp.all(x == identity3(x))
      assert jnp.all(x == identity4(x))
  
imports: import warnings
  from typing import Union
  import equinox
  import jax
  import jax.nn
  import jax.numpy
  import jax.random
  import pytest
label_desc: Use image node_id 3 for calling a global function with example usage: test_identity(getkey) without return types