code: def getVolumes(self, obj=None, renderer=None):
          
          if renderer is None:
              renderer = self.renderer
          elif isinstance(renderer, int):
                  renderer = self.renderers.index(renderer)
          else:
              return []
          
          if obj is None or isinstance(obj, int):
              if obj is None:
                  acs = renderer.GetVolumes()
              elif obj >= len(self.renderers):
                  colors.printc("~timesError in getVolumes: non existing renderer", obj, c=1)
                  return []
              else:
                  acs = self.renderers[obj].GetVolumes()
              vols = []
              acs.InitTraversal()
              for i in range(acs.GetNumberOfItems()):
                  a = acs.GetNextItem()
                  if a.GetPickable():
                      r = self.renderers.index(renderer)
                      if a == self.axes_exist[r]:
                          continue
                      vols.append(a)
              return vols
docs: Return the list of the rendered Volumes.