WooCommerce Checkout Fields

I’m trying to remove the shipping-country field.

This is the code..

add_filter( 'woocommerce_default_address_fields' , 'custom_override_checkout_fields' );

function custom_override_checkout_fields( $fields ) {
     unset($fields['shipping']['shipping_country']);
    unset($fields['shipping']['shipping_state']);
     return $fields;
}