class_docstr: Model used to check cpu offload memory saving
class_docstr_tok: ["Model","used","to","check","cpu","offload","memory","saving"]
code: def forward(self, x):
      return self.layers(x)
  
imports: import pytest
  import torch
  import torch.nn
  from torch.utils.checkpoint import checkpoint
  from fairscale.fair_dev.testing.testing import skip_if_no_cuda
  from fairscale.internal import torch_version
  from fairscale.nn.checkpoint.checkpoint_activations import checkpoint_wrapper, disable_checkpointing
  from fairscale.nn.misc import FlattenParamsWrapper
  from fairscale.nn.misc import checkpoint_wrapper
label_desc: Use image node_id 2 for calling the CpuOffloadModel obj's underlying member method code with example usage: obj.forward(x) and returns: self