WooCommerce: Select default payment gateway option on checkout page

woocommerce_default_payment_gateway.php

/**
 * Select Stripe as default payment gateway
 */
add_action( 'woocommerce_before_checkout_form', 'set_default_gateway' );
function set_default_gateway(){
    // HERE define the default payment gateway ID
    $default_payment_gateway_id = 'stripe';

    WC()->session->set('chosen_payment_method', $default_payment_gateway_id);
}