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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def Copy(self, field_number=None):
 """Returns descriptor copy, optionally changing field number."""

    new_args = self._kwargs.copy()
    if field_number is not None:
      new_args["field_number"] = field_number

    return ProtoRDFValue(
        rdf_type=self.original_proto_type_name,
        default=getattr(self, "default", None),
        **new_args)