code: def native(self):
          
  
          # For BitString we default the value to be all zeros
          if self.contents is None:
              if self._map is None:
                  self.set(())
              else:
                  self.set(set())
  
          if self._native is None:
              bits = self._merge_chunks()
              if self._map:
                  self._native = set()
                  for index, bit in enumerate(bits):
                      if bit:
                          name = self._map.get(index, index)
                          self._native.add(name)
              else:
                  self._native = bits
          return self._native
docs: The native Python datatype representation of this value
  
          :return:
              If a _map is set, a set of names, or if no _map is set, a tuple of
              integers 1 and 0. None if no value.