How to Hide Cube 3D Slider Admin Menus

function plt_hide_cube_3d_slider_menus() {
	//Hide the "Cube 3D Sliders" menu.
	remove_menu_page('cube_3d_sliders');
	//Hide the "Cube 3D Sliders → Cube 3D Sliders" menu.
	remove_submenu_page('cube_3d_sliders', 'cube_3d_sliders');
	//Hide the "Cube 3D Sliders → Help" menu.
	remove_submenu_page('cube_3d_sliders', 'cube_3d_sliders_help');
}

add_action('admin_menu', 'plt_hide_cube_3d_slider_menus', 11);

Where do I put this code?