Add button to buy the product grid WooCommerce

functions.php

//Add button to buy the product grid WooCommerce 
remove_action( 'woocommerce_after_shop_loop_item', 'woocommerce_template_loop_add_to_cart', 10 ); 
add_action( 'woocommerce_after_shop_loop_item', 'my_woocommerce_template_loop_add_to_cart', 10 ); 

    function my_woocommerce_loop_add_to_cart() 
      { 
         global $product; 
         echo '<form action="' . esc_url( $product->get_permalink( $product->id ) ) . '" method="get"> 
         <button type="submit" class="single_add_to_cart_button button alt">' . __('Comprar', 'woocommerce') . '</button> 
         </form>';
      }