public function atualizarContato($id, $nome, $email)
 {
     $sql = "UPDATE contatos SET nome=?, email=? WHERE id=?";
     try {
         $dbCon = getConnection();
         $stmt = $dbCon->prepare($sql);
         $stmt->bindParam(1, $nome);
         $stmt->bindParam(2, $email);
         $stmt->bindParam(3, $id);
         $stmt->execute();
         $contato = new Contato($nome, $email);
         $contato->setId($id);
         $dbCon = null;
         return $contato;
     } catch (PDOException $e) {
         echo '{"error":{"text":' . $e->getMessage() . '}}';
     }
 }