code: def forward(
      model: Model, X: Any, is_train: bool
  ) -> Tuple[Any, Callable]:
      cpu_outputs, backprop = model.layers[0].begin_update(_to_cpu(X))
      gpu_outputs = _to_device(model.ops, cpu_outputs)
  
      def with_cpu_backprop(d_outputs):
          cpu_d_outputs = _to_cpu(d_outputs)
          return backprop(cpu_d_outputs)
  
      return gpu_outputs, with_cpu_backprop
  
file_path: thinc/thinc/layers/with_cpu.py
imports: from typing import Any, Callable, Tuple
  import numpy
  from thinc.backends import Ops
  from ..config import registry
  from ..model import Model
label_desc: Use image node_id 2 for calling a global function with example usage: forward(model, X, is_train) and returns: gpu_outputs,  with_cpu_backprop, backprop