code: def set_scale(self, xscale=None, yscale=None, zscale=None, reset_camera=True):
          
          self.renderer.set_scale(xscale, yscale, zscale, reset_camera)
docs: Scale all the datasets in the scene of the active renderer.
  
          Scaling in performed independently on the X, Y and Z axis.
          A scale of zero is illegal and will be replaced with one.
  
          Parameters
          ----------
          xscale : float, optional
              Scaling of the x axis.  Must be greater than zero.
  
          yscale : float, optional
              Scaling of the y axis.  Must be greater than zero.
  
          zscale : float, optional
              Scaling of the z axis.  Must be greater than zero.
  
          reset_camera : bool, optional
              Resets camera so all actors can be seen.