def Copy(self, field_number=None):
    result = copy.copy(self)
    if field_number is not None:
      result.field_number = field_number
      result.CalculateTags()

    return result
Returns a copy of descriptor, optionally changing the field number.
dataset/ETHPy150Open google/grr/grr/lib/rdfvalues/structs.py/ProtoType.Copy