code: def _split_overlays(self):
          "Splits overlays inside the HoloMap into list of HoloMaps"
          if not issubclass(self.type, CompositeOverlay):
              return None, self.clone()
  
          item_maps = OrderedDict()
          for k, overlay in self.data.items():
              for key, el in overlay.items():
                  if key not in item_maps:
                      item_maps[key] = [(k, el)]
                  else:
                      item_maps[key].append((k, el))
  
          maps, keys = [], []
          for k, layermap in item_maps.items():
              maps.append(self.clone(layermap))
              keys.append(k)
          return keys, mapf _split_overlays(self):
          "Splits overlays inside the HoloMap into list of HoloMaps"
          if not issubclass(self.type, CompositeOverlay):
              return None, self.clone()
  
          item_maps = OrderedDict()
          for k, overlay in self.data.items():
              for key, el in overlay.items():
                  if key not in item_maps:
                      item_maps[key] = [(k, el)]
                  else:
                      item_maps[key].append((k, el))
  
          maps, keys = [], []
          for k, layermap in item_maps.items():
              maps.append(self.clone(layermap))
              keys.append(k)
          return keys, maps
docs: Splits overlays inside the HoloMap into list of HoloMaps