/**
  * @return void
  */
 private function clearUsers()
 {
     $users = $this->client->getUsers();
     while (count($users['entities']) > 0) {
         foreach ($users['entities'] as $user) {
             $this->client->deleteUser($user['id'], true);
         }
         $users = $this->client->getUsers();
     }
 }