Add custom Pretty Link to Custom Post Type or Custom Taxonomy

wp_permasctructs

<?php
/**
  * Add custom Pretty Link to Custom Post Type or Custom Taxonomy
  *
  * Change @@@ to your CPT or CT slug...
  *
  * Change ??? to custom link like example or anything else...
  *
*/
function wp_permastructs(){
  global $wp_rewrite;
  $wp_rewrite->extra_permastructs['@@@']['struct'] = '???/%@@@%/';
}
add_action( 'init', 'wp_permastructs' );