How to Hide Participants Database Admin Menus

function plt_hide_participants_database_menus() {
	//Hide "Participants Database".
	remove_menu_page('participants-database');
	//Hide "Participants Database → List Participants".
	remove_submenu_page('participants-database', 'participants-database');
	//Hide "Participants Database → Add Participant".
	remove_submenu_page('participants-database', 'participants-database-add_participant');
	//Hide "Participants Database → Manage Database Fields".
	remove_submenu_page('participants-database', 'participants-database-manage_fields');
	//Hide "Participants Database → Manage List Columns".
	remove_submenu_page('participants-database', 'participants-database-manage_list_columns');
	//Hide "Participants Database → Import CSV File".
	remove_submenu_page('participants-database', 'participants-database-upload_csv');
	//Hide "Participants Database → Settings".
	remove_submenu_page('participants-database', 'participants-database_settings_page');
	//Hide "Participants Database → Setup Guide".
	remove_submenu_page('participants-database', 'participants-database-setup_guide');
	//Hide "Participants Database → Debugging Log".
	remove_submenu_page('participants-database', 'participants-database-pdb_debugging');
}

add_action('admin_menu', 'plt_hide_participants_database_menus', 13);

Where do I put this code?