code: function toString()
      {
  
          // Generate custom field string
          $customfields = "";
          if (isset($this->custom_fields)) {
              foreach ($this->custom_fields as $index => $type) {
                  $customfields .= $index . "=" . $type . ", ";
              }
              $customfields = rtrim($customfields, ', ');
          }
  
          return "CustomFields = {" . $customfields . "}";
      }
docs: Human readable representation of this list of custom fields.
  
  @return \em string
  The human readable representation of the list of custom fields.