code: def _convert_operator(self, node_name, op_name, attrs, inputs):
          
          if op_name in convert_map:
              op_name, new_attrs, inputs = convert_map[op_name](attrs, inputs, self)
          else:
              raise NotImplementedError("Operator {} not implemented.".format(op_name))
          if isinstance(op_name, string_types):
              new_op = getattr(symbol, op_name, None)
              if not new_op:
                  raise RuntimeError("Unable to map op_name {} to sym".format(op_name))
              if node_name is None:
                  mxnet_sym = new_op(*inputs, **new_attrs)
              else:
                  mxnet_sym = new_op(name=node_name, *inputs, **new_attrs)
              return mxnet_sym
          return op_name
docs: Convert from onnx operator to mxnet operator.
          The converter must specify conversions explicitly for incompatible name, and
          apply handlers to operator attributes.
  
          Parameters
          ----------
          :param node_name : str
              name of the node to be translated.
          :param op_name : str
              Operator name, such as Convolution, FullyConnected
          :param attrs : dict
              Dict of operator attributes
          :param inputs: list
              list of inputs to the operator
          Returns
          -------
          :return mxnet_sym
              Converted mxnet symbol