code: private static void putIntoMultiMap(Map<ResourceID, List<SharedSlot>> map, ResourceID location, SharedSlot slot) {
  		List<SharedSlot> slotsForInstance = map.get(location);
  		if (slotsForInstance == null) {
  			slotsForInstance = new ArrayList<SharedSlot>();
  			map.put(location, slotsForInstance);
  		}
  		slotsForInstance.add(slot);
  	}
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