code: def smoothed(self, angle=.4):
          
  
          # smooth should be recomputed if visuals change
          self.visual._verify_crc()
          cached = self.visual._cache['smoothed']
          if cached is not None:
              return cached
  
          smoothed = graph.smoothed(self, angle)
          self.visual._cache['smoothed'] = smoothed
          return smoothed
docs: Return a version of the current mesh which will render
          nicely, without changing source mesh.
  
          Parameters
          -------------
          angle : float
            Angle in radians, face pairs with angles smaller than
            this value will appear smoothed
  
          Returns
          ---------
          smoothed : trimesh.Trimesh
            Non watertight version of current mesh
            which will render nicely with smooth shading