docs: def is_connected(self, other):
          """
          Returns ``True`` if there exists a (possibly empty) range which is
          enclosed by both this range and other.
  
          Examples:
  
          * [1, 3] and [5, 7] are not connected
          * [5, 7] and [1, 3] are not connected
          * [2, 4) and [3, 5) are connected, because both enclose [3, 4)
          * [1, 3) and [3, 5) are connected, because both enclose the empty range
            [3, 3)
          * [1, 3) and (3, 5) are not connected
          """
          return self.upper > other.lower and other.upper > self.lower or (
              self.upper == other.lower and (self.upper_inc or other.lower_inc)
          ) or (
              self.lower == other.upper and (self.lower_inc or other.upper_inc)
          )