//Sets the spawn structure at y 60
setSpawnStructure("basic tree", 60)

//Creates a new LayerGenerator and saves it as a variable
layers = new LayerGenerator()

//Adds a layer of bedrock in y 0
layers.addLayer(0~0, <minecraft:bedrock>)

//Adds a layer of water from y 1 to y 60
layers.addLayer(1~60, <minecraft:water>)

//Adds the layer generator to the dimension
addGenerator(layers)