Determine if WordPress user is a WooCommerce shop manager

/*
 * Function determines if WordPress user (current or by ID) is a WooCommerce shop manager.
 *
 * @return bool
 */
function is_shop_manager( $user_id = 0 ) {
	$the_user = ( 0 == $user_id ) ? wp_get_current_user() : get_user_by( 'id', $user_id );
	return ( isset( $the_user->roles[0] ) && 'shop_manager' === $the_user->roles[0] ) ? true : false;
}