code: def test_zero_layer(self):
      # if the wrapped layer outputs zero, the residual block should be an identity mapping
      class ZeroLayer(nn.Module):
          def __init__(self):
              super().__init__()
  
          def forward(self, x: torch.Tensor) -> torch.Tensor:
              return torch.zeros_like(x)
  
      zero_layer = ZeroLayer()
      wrapped_layer = ResidualWrapper(zero_layer)
  
      x = torch.randn(2, 3)
      y = wrapped_layer(x)
      npt.assert_array_equal(x.detach().numpy(), y.detach().numpy())
  
file_path: ReAgent/reagent/test/models/test_residual_wrapper.py
imports: import unittest
  import numpy.testing
  import torch
  import torch.nn
  from reagent.models.residual_wrapper import ResidualWrapper
label_desc: Use image node_id 1 for calling the TestResidualWrapper obj's underlying member method code with example usage: obj.test_zero_layer() and returns: torch