WC Apply a different tax rate based on the user role

gistfile1.txt

/**
 * Apply a different tax rate based on the user role. Updated 2017
 */
function wc_diff_rate_for_user( $tax_class, $product ) {
        $user_id = get_current_user_id();
        $user_data = get_userdata($user_id);
    if ( is_user_logged_in() &&
            in_array( 'au_export_trade_45', $user_data->roles ) ||
            in_array( 'row_trade_45', $user_data->roles ) ||
            in_array( 'row_distributor', $user_data->roles ) ||
            in_array( 'eu_ext_trade_45', $user_data->roles ) ||
            in_array( 'row_trade_45', $user_data->roles ) ||
            in_array( 'us_distributor_50', $user_data->roles ) ||
            in_array( 'us_trade_40', $user_data->roles )) {
        $tax_class = 'Zero Rate';
    }
    return $tax_class;
}
add_filter( 'woocommerce_product_tax_class', 'wc_diff_rate_for_user', 1, 2 );