code: def _create_dynamic_subplots(self, key, items, ranges, **init_kwargs):
          
          length = self.style_grouping
          group_fn = lambda x: (x.type.__name__, x.last.group, x.last.label)
          for i, (k, obj) in enumerate(items):
              vmap = self.hmap.clone([(key, obj)])
              self.map_lengths[group_fn(vmap)[:length]] += 1
              subplot = self._create_subplot(k, vmap, [], ranges)
              if subplot is None:
                  continue
              self.subplots[k] = subplot
              subplot.initialize_plot(ranges, **init_kwargs)
              subplot.update_frame(key, ranges, element=obj)
              self.dynamic_subplots.append(subplot)
docs: Handles the creation of new subplots when a DynamicMap returns
          a changing set of elements in an Overlay.