Hide paypal based on shipping methods - Woocommerce

hide-payment-woocommerce.php

<?php
function alter_shipping_methods($available_gateways){
    global $woocommerce;
    $chosen_titles = array();
    $available_methods = $woocommerce->shipping->get_packages();
    $chosen_rates = ( isset( $woocommerce->session ) ) ? $woocommerce->session->get( 'chosen_shipping_methods' ) : array();

    foreach ($available_methods as $method)
           foreach ($chosen_rates as $chosen) {
                if( isset( $method['rates'][$chosen] ) ) $chosen_titles[] = $method['rates'][ $chosen ]->label;
            }
    if( in_array( 'First-Class Mail&#0174; (USPS)', $chosen_titles ) ) {
    	unset($available_gateways['paypal']);
    }
    return $available_gateways;
}

add_action('woocommerce_available_payment_gateways', 'alter_shipping_methods');