code: def section_multiplane(self,
                             plane_origin,
                             plane_normal,
                             heights):
          
          # turn line segments into Path2D/Path3D objects
          from .exchange.load import load_path
          # do a multiplane intersection
          lines, transforms, faces = intersections.mesh_multiplane(
              mesh=self,
              plane_normal=plane_normal,
              plane_origin=plane_origin,
              heights=heights)
  
          # turn the line segments into Path2D objects
          paths = [None] * len(lines)
          for index, L, T in zip(range(len(lines)),
                                 lines,
                                 transforms):
              if len(L) > 0:
                  paths[index] = load_path(
                      L, metadata={'to_3D': T})
          return paths
docs: Return multiple parallel cross sections of the current
          mesh in 2D.
  
          Parameters
          ---------
          plane_normal: (3) vector for plane normal
            Normal vector of section plane
          plane_origin : (3,) float
            Point on the cross section plane
          heights : (n,) float
            Each section is offset by height along
            the plane normal.
  
          Returns
          ---------
          paths : (n,) Path2D or None
            2D cross sections at specified heights.
            path.metadata['to_3D'] contains transform
            to return 2D section back into 3D space.