code: def intersect_range(self, start=None, stop=None):
          
  
          try:
              loc = self.locate_range(start=start, stop=stop)
          except KeyError:
              return self.values[0:0]
          else:
              return self[loc]
docs: Intersect with range defined by `start` and `stop` values
          **inclusive**.
  
          Parameters
          ----------
          start : int, optional
              Start value.
          stop : int, optional
              Stop value.
  
          Returns
          -------
          idx : SortedIndex
  
          Examples
          --------
  
          >>> import allel
          >>> idx = allel.SortedIndex([3, 6, 11, 20, 35])
          >>> idx.intersect_range(4, 32)
          <SortedIndex shape=(3,) dtype=int64>
          [6, 11, 20]