private static void InternalPushNet(IntPtr state, object obj, string metatable)
{
var handle = GCHandle.Alloc(obj, GCHandleType.Normal);
LuaApi.PushHandle(state, handle);
LuaApi.GetField(state, LuaApi.RegistryIndex, metatable);
LuaApi.SetMetatable(state, -2);
}