code: def clone_with_native_proposal_layer(model):
      def filter(x):
          return (
              type(x) == C.Function
              and x.op_name == "UserFunction"
              and x.name == "ProposalLayer"
          )
  
      def converter(x):
          layer_config = copy.deepcopy(x.attributes)
          return ops.native_user_function(
              "ProposalLayerOp",
              list(x.inputs),
              layer_config,
              "native_proposal_layer",
          )
  
      return C.misc.convert(model, filter, converter)
  
imports: import os, sys, argparse, copy
  import cntk
  from cntk import ops
label_desc: Use image node_id 1 for calling a global function with example usage: clone_with_native_proposal_layer(model) and returns: C, unknown, ops