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<?php

/**
 * This adds the new unit to the WooCommerce admin
 */
function add_woocommerce_dimension_unit_league( $settings ) {

	foreach ( $settings as &$setting ) {

		if ( 'woocommerce_dimension_unit' == $setting['id'] ) {
			$setting['options']['league'] = __( 'League' );  // new unit
		}
	}

	return $settings;
}
add_filter( 'woocommerce_product_settings', 'add_woocommerce_dimension_unit_league' );