code: def prepare(cls, model, device="CPU", **kwargs):
      expected_out_types = [
          out.type.tensor_type.elem_type for out in model.graph.output
      ]
      with open(r"tmp_model.pb", "wb") as f:
          f.write(model.SerializeToString())
  
      CNTKBackend.set_device(device)
      c_model = C.Function.load(
          r"tmp_model.pb", format=C.ModelFormat.ONNX
      )
      return CNTKBackendRep(c_model, expected_out_types)
  
file_path: CNTK/bindings/python/onnx_cntk/backend.py
imports: import cntk
  import numpy
  from onnx import helper, TensorProto
  from onnx.backend.base import Backend
  from onnx.backend.base import BackendRep
label_desc: Use image node_id 3 for calling the CNTKBackend obj's underlying member method code with example usage: obj.prepare(cls, model, device) and returns: CNTKBackendRep