Creating terrain from script

I know that this question has been solved before, but I cannot locate the actual answer. I have created some TerrainData in script and saved it as an asset. This all works really well. I am now trying to create Terrain from this TerrainData. I know that there is the method CreateTerrainGameObject(TerrainData) but every time I try to use it, Unity gives me the error 'Insert semicolon at end'. Here is the particular line:

 GameObject g = Terrain.CreateTerrainGameObject(terrainData));

If I comment this line out, my script throws no errors. Any help would be greatly appreciated!