How to use the crypten.mpc.set_default_provider function in crypten

"""Tests tensor encoding and decoding."""
        for float in [False, True]:
            if float:
                fpe = FixedPointEncoder(precision_bits=16)
            else:
                fpe = FixedPointEncoder(precision_bits=0)
            tensor = get_test_tensor(float=float)
            decoded = fpe.decode(fpe.encode(tensor))
            self._check(
                decoded,
                tensor,
                "Encoding/decoding a %s failed." % "float" if float else "long",
            )

        # Make sure encoding a subclass of CrypTensor is a no-op
        crypten.mpc.set_default_provider(crypten.mpc.provider.TrustedFirstParty)
        crypten.init()

        tensor = get_test_tensor(float=True)
        encrypted_tensor = crypten.cryptensor(tensor)
        encrypted_tensor = fpe.encode(encrypted_tensor)
        self._check(
            encrypted_tensor.get_plain_text(),
            tensor,
            "Encoding an EncryptedTensor failed.",
        )

        # Try a few other types.
        fpe = FixedPointEncoder(precision_bits=0)
        for dtype in [torch.uint8, torch.int8, torch.int16]:
            tensor = torch.zeros(5, dtype=dtype).random_()
            decoded = fpe.decode(fpe.encode(tensor)).type(dtype)

def test_in_first(self):
        # TODO: Make this work with TTP provider
        crypten.mpc.set_default_provider(crypten.mpc.provider.TrustedFirstParty)

        # This will cause the parent process to init with world-size 1
        crypten.init()
        self.assertEqual(comm.get().get_world_size(), 1)

        # This will fork 2 children which will have to init with world-size 2
        self.assertEqual(test_rank_func(), [0, 1])

        # Make sure everything is the same in the parent
        self.assertEqual(comm.get().get_world_size(), 1)

def setUp(self):
        self._original_provider = crypten.mpc.get_default_provider()
        crypten.mpc.set_default_provider(crypten.mpc.provider.TrustedFirstParty)
        super(TestTFP, self).setUp()

def setUp(self):
        self._original_provider = crypten.mpc.get_default_provider()
        crypten.mpc.set_default_provider(crypten.mpc.provider.TrustedThirdParty)
        super(TestTTP, self).setUp()

def tearDown(self):
        crypten.mpc.set_default_provider(self._original_provider)
        super(TestTFP, self).tearDown()

def setUp(self):
        self._original_provider = crypten.mpc.get_default_provider()
        crypten.mpc.set_default_provider(crypten.mpc.provider.TrustedFirstParty)
        super(TestTFP, self).setUp()

def setUp(self):
        self._original_provider = crypten.mpc.get_default_provider()
        crypten.mpc.set_default_provider(crypten.mpc.provider.TrustedThirdParty)
        super(TestTTP, self).setUp()

def tearDown(self):
        crypten.mpc.set_default_provider(self._original_provider)
        super(TestTTP, self).tearDown()

def setUp(self):
        self._original_provider = crypten.mpc.get_default_provider()
        crypten.mpc.set_default_provider(crypten.mpc.provider.TrustedThirdParty)
        super(TestTTP, self).setUp()