function gettplLettersList($params = array(), $response = array())
 {
     global $wpdb;
     $table_name = TemplateData::get_tpl_letters_table_name();
     $query = "SELECT id, form_id, is_active, meta FROM {$table_name}";
     $where = "";
     if (isset($params['where'])) {
         $where[] = $params['where'];
     }
     if (!empty($where)) {
         $query .= " where " . implode(" and ", $where);
     }
     $response = $wpdb->get_results($query, ARRAY_A);
     if (empty($response)) {
         return array();
     }
     $response = $response[0];
     $response["meta"] = maybe_unserialize($response["meta"]);
     return $response;
 }