code: def curve_primitive(self):
          
          curve = self.curve
          curve.axis_start = self.helix_start
          curve.axis_end = self.helix_end
          coords = curve.get_coords(
              n_points=(self.num_monomers + 1), spacing=self.minor_rise_per_residue)
          if self.orientation == -1:
              coords.reverse()
          return Primitive.from_coordinates(coords)
docs: `Primitive` of the super-helical curve.