def testAddClient(self):
        client1 = Client(1, "Name1")
        client2 = Client(1, "Name2")
        repo = Repository()
        functions = ClientController(repo, Statistics(repo))

        msg1 = functions.addClient(client1.getId(), client1.getName())
        self.assertTrue(len(msg1) == 0)
        self.assertTrue(functions.getClients()[0].getId() == 1)

        msg2 = functions.addClient(client2.getId(), client2.getName())
        self.assertTrue(msg2 == "Cannot add an existing element")

        self.assertTrue(functions.getClients()[0].getId() == 1)
    def testRemoveClient(self):
        client1 = Client(1, "Name1")
        client2 = Client(2, "Name2")
        repo = Repository()
        functions = ClientController(repo, Statistics(repo))

        functions.addClient(client1.getId(), client1.getName())
        functions.addClient(client2.getId(), client2.getName())

        msg1 = functions.removeClient(1)

        self.assertTrue(len(msg1) == 0)
        self.assertTrue(functions.getClients()[0].getId() == client2.getId())
        self.assertTrue(functions.getClients()[0].getName() == client2.getName())

        msg2 = functions.removeClient(1)

        self.assertTrue(msg2 == "The provided ID does not exist")
        self.assertTrue(functions.getClients()[0].getId() == client2.getId())
        self.assertTrue(functions.getClients()[0].getName() == client2.getName())