How to use the pysodium.sodium_version_check function in pysodium

def test_crypto_core_ristretto255_scalar_random(self):
        if not pysodium.sodium_version_check(1, 0, 18): return
        a = pysodium.crypto_core_ristretto255_scalar_random()
        b = pysodium.crypto_core_ristretto255_scalar_random()
        # stupid check that random returns different values...
        self.assertNotEqual(a,b)

def test_crypto_secretstream_xchacha20poly1305_init_push(self):
        if not pysodium.sodium_version_check(1, 0, 15): return

        key = pysodium.crypto_secretstream_xchacha20poly1305_keygen()
        state, header = pysodium.crypto_secretstream_xchacha20poly1305_init_push(key)

def test_aead_chacha20poly1305_ietf(self):
        if not pysodium.sodium_version_check(1, 0, 4): return
        key = binascii.unhexlify(b"4290bcb154173531f314af57f3be3b5006da371ece272afa1b5dbdd1100a1007")
        input_ = binascii.unhexlify(b"86d09974840bded2a5ca")
        nonce = binascii.unhexlify(b"cd7cf67be39c794acd7cf67b")
        for ad in [binascii.unhexlify(b"87e229d4500845a079c0"), None]:
            output = pysodium.crypto_aead_chacha20poly1305_ietf_encrypt(input_, ad, nonce, key)
            output = pysodium.crypto_aead_chacha20poly1305_ietf_decrypt(output, ad, nonce, key)
            self.assertEqual(output, input_)

def test_crypto_secretstream_xchacha20poly1305_rekey(self):
        if not pysodium.sodium_version_check(1, 0, 15): return

        key = pysodium.crypto_secretstream_xchacha20poly1305_keygen()
        state, header = pysodium.crypto_secretstream_xchacha20poly1305_init_push(key)

        # Encrypt two messages with intermediate re-key
        ciphertext = pysodium.crypto_secretstream_xchacha20poly1305_push(state, b"Correct Horse Battery Staple", None, 0)
        pysodium.crypto_secretstream_xchacha20poly1305_rekey(state)
        ciphertext2 = pysodium.crypto_secretstream_xchacha20poly1305_push(state, b"howdy", None, pysodium.crypto_secretstream_xchacha20poly1305_TAG_FINAL)

        # Verify by decrypting them
        state2 = pysodium.crypto_secretstream_xchacha20poly1305_init_pull(header, key)
        msg, tag = pysodium.crypto_secretstream_xchacha20poly1305_pull(state2, ciphertext, None)
        pysodium.crypto_secretstream_xchacha20poly1305_rekey(state2)
        msg2, tag2 = pysodium.crypto_secretstream_xchacha20poly1305_pull(state2, ciphertext2, None)

        self.assertEqual(msg, b"Correct Horse Battery Staple")

def test_aead_chacha20poly1305_detached(self):
        if not pysodium.sodium_version_check(1, 0, 9): return
        key = binascii.unhexlify(b"4290bcb154173531f314af57f3be3b5006da371ece272afa1b5dbdd1100a1007")
        input_ = binascii.unhexlify(b"86d09974840bded2a5ca")
        nonce = binascii.unhexlify(b"cd7cf67be39c794a")
        for ad, ct in [
                (binascii.unhexlify(b"87e229d4500845a079c0"), b"677dabf4e3d24b876bb284753896e1d6"),
                (None,                                        b"69e7789bcd954e658ed38423e23161dc"),
        ]:
            output, mac = pysodium.crypto_aead_chacha20poly1305_encrypt_detached(input_, ad, nonce, key)
            self.assertEqual(binascii.unhexlify(b"e3e446f7ede9a19b62a4"), output)
            self.assertEqual(binascii.unhexlify(ct), mac)
            output = pysodium.crypto_aead_chacha20poly1305_decrypt_detached(output, mac, ad, nonce, key)
            self.assertEqual(output, input_)

def test_crypto_pwhash(self):
        if not pysodium.sodium_version_check(1, 0, 9): return
        pw = "Correct Horse Battery Staple"
        salt = binascii.unhexlify(b'0f58b94c7a369fd8a9a7083e4cd75266')
        out = pysodium.crypto_pwhash(pysodium.crypto_auth_KEYBYTES, pw, salt, pysodium.crypto_pwhash_argon2i_OPSLIMIT_INTERACTIVE, pysodium.crypto_pwhash_argon2i_MEMLIMIT_INTERACTIVE, pysodium.crypto_pwhash_ALG_ARGON2I13)
        self.assertEqual(binascii.hexlify(out), b'79db3095517c7358449d84ee3b2f81f0e9907fbd4e0bae4e0bcc6c79821427dc')

def test_crypto_scalarmult_ristretto255_base(self):
        if not pysodium.sodium_version_check(1, 0, 18): return
        p = pysodium.crypto_scalarmult_ristretto255_base(pysodium.crypto_core_ristretto255_scalar_random())
        pysodium.crypto_core_ristretto255_is_valid_point(p)

def test_crypto_secretstream_xchacha20poly1305_pull_corrupted(self):
        if not pysodium.sodium_version_check(1, 0, 15): return

        key = pysodium.crypto_secretstream_xchacha20poly1305_keygen()
        state, header = pysodium.crypto_secretstream_xchacha20poly1305_init_push(key)

        ad = 'additional data'
        ciphertext = pysodium.crypto_secretstream_xchacha20poly1305_push(state, b"Correct Horse Battery Staple", ad, 0)

        # Verify error is raised if cypher text is changed
        state2 = pysodium.crypto_secretstream_xchacha20poly1305_init_pull(header, key)
        self.assertRaises(ValueError, pysodium.crypto_secretstream_xchacha20poly1305_pull, state2, ciphertext + 'this is a corruption'.encode(), ad)

        # Verify error is raised if additional data is changed
        ad2 = 'this is not the same'
        state2 = pysodium.crypto_secretstream_xchacha20poly1305_init_pull(header, key)
        self.assertRaises(ValueError, pysodium.crypto_secretstream_xchacha20poly1305_pull, state2, ciphertext, ad2)

def test_crypto_pwhash_storage(self):
        if not pysodium.sodium_version_check(1, 0, 9): return
        pw = "Correct Horse Battery Staple"
        pstr = pysodium.crypto_pwhash_str(pw, pysodium.crypto_pwhash_OPSLIMIT_INTERACTIVE, pysodium.crypto_pwhash_MEMLIMIT_INTERACTIVE)
        self.assertTrue(pysodium.crypto_pwhash_str_verify(pstr, pw))

def test_crypto_secretstream_xchacha20poly1305_pull_incorrect_key(self):
        if not pysodium.sodium_version_check(1, 0, 15): return

        key = pysodium.crypto_secretstream_xchacha20poly1305_keygen()
        state, header = pysodium.crypto_secretstream_xchacha20poly1305_init_push(key)
        ciphertext = pysodium.crypto_secretstream_xchacha20poly1305_push(state, b"howdy", None, pysodium.crypto_secretstream_xchacha20poly1305_TAG_FINAL)

        bad_key = pysodium.crypto_secretstream_xchacha20poly1305_keygen()
        state2 = pysodium.crypto_secretstream_xchacha20poly1305_init_pull(header, bad_key)
        self.assertRaises(ValueError, pysodium.crypto_secretstream_xchacha20poly1305_pull, state2, ciphertext, None)