code: def get_bounds(self):
          
          if self._vertices_indexed_by_faces is not None:
              v = self._vertices_indexed_by_faces
          elif self._vertices is not None:
              v = self._vertices
          else:
              return None
          bounds = [(v[:, ax].min(), v[:, ax].max()) for ax in range(v.shape[1])]
          return bounds
docs: Get the mesh bounds
  
          Returns
          -------
          bounds : list
              A list of tuples of mesh bounds.