code: def test_module_cache():
      class Child(PyroModule):
          def __init__(self, x):
              super().__init__()
              self.a = PyroParam(torch.tensor(x))
  
          def forward(self):
              return self.a
  
      class Family(PyroModule):
          def __init__(self):
              super().__init__()
              self.c = Child(1.0)
  
          def forward(self):
              return self.c.a
  
      f = Family()
      assert_equal(f().detach(), torch.tensor(1.0))
      f.c = Child(3.0)
      assert_equal(f().detach(), torch.tensor(3.0))
      assert_equal(f.c().detach(), torch.tensor(3.0))
  
imports: import io
  import warnings
  import pytest
  import torch
  from torch import nn
  from torch.distributions import constraints, transform_to
  import pyro
  import pyro.distributions
  from pyro import poutine
  from pyro.infer import SVI, Trace_ELBO
  from pyro.nn.module import PyroModule, PyroParam, PyroSample, clear, to_pyro_module_
  from pyro.optim import Adam
  from tests.common import assert_equal
label_desc: Use image node_id 7 for calling a global function with example usage: test_module_cache() and returns: self, self