How to Hide Stripe Payment Gateway Admin Menus

function plt_hide_gateway_stripe_menus() {
	//Hide the "Stripe Gateway" menu.
	remove_menu_page('stripe-gateway-page');
	//Hide the "Stripe Gateway → Settings" menu.
	remove_submenu_page('stripe-gateway-page', 'stripe-gateway-settings');
	//Hide the "Stripe Gateway → Log Entries" menu.
	remove_submenu_page('stripe-gateway-page', 'stripe-gateway-logs');
}

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

Where do I put this code?