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Schematic To Command Block - A utility for Minecraft that will convert .schematic or .nbt structure files into commands that can be run in command blocks that will create the structure in game
For more information on how to use the utility, either read the instructions when you run the utility (if you have java 1.8 or higher installed, you should be able to just double click the the .jar file to run it), or watch this video: https://www.youtube.com/watch?v=336StADsKO0