Standardmäßig konvertiert **FastAPI** diesen Rückgabewert automatisch nach JSON, mithilfe des `jsonable_encoder`, der in [JSON-kompatibler Encoder](../tutorial/encoder.md){.internal-link target=_blank} erläutert wird.

Dann würde es hinter den Kulissen diese JSON-kompatiblen Daten (z. B. ein `dict`) in eine `JSONResponse` einfügen, die zum Senden der Response an den Client verwendet würde.

     * @param machineId the machine identifier (32 bytes)
     */
    public AvSingleHost(final byte[] customData, final byte[] machineId) {
        this(encode(customData, machineId));
    }

    private static byte[] encode(final byte[] customData, final byte[] machineId) {
        final int size = 8 + 8 + 32;
        final byte[] enc = new byte[size];
        SMBUtil.writeInt4(size, enc, 0);

    }

    @Test
    @DisplayName("encode without andx succeeds and signs when digest present")
    void testEncodeNoAndxWithSigning() throws Exception {
        DummyAndXBlock block = new DummyAndXBlock();
        TestSigningDigest digest = new TestSigningDigest();
        block.digest = digest;

        byte[] buf = new byte[256];
        int len = block.encode(buf, 0);

        assertTrue(len > 0);

Por padrão, o **FastAPI** irá converter automaticamente o valor do retorno para JSON utilizando o `jsonable_encoder` explicado em [JSON Compatible Encoder](../tutorial/encoder.md){.internal-link target=_blank}.

Então, por baixo dos panos, ele incluiria esses dados compatíveis com JSON (e.g. um `dict`) dentro de uma `JSONResponse` que é utilizada para enviar uma resposta para o cliente.

// ScanRunes is a split function for a [Scanner] that returns each
// UTF-8-encoded rune as a token. The sequence of runes returned is
// equivalent to that from a range loop over the input as a string, which
// means that erroneous UTF-8 encodings translate to U+FFFD = "\xef\xbf\xbd".
// Because of the Scan interface, this makes it impossible for the client to
// distinguish correctly encoded replacement runes from encoding errors.

        buf.enc_ndr_small(1); /* number of items */
        buf.enc_ndr_small(0); /* reserved */
        this.binding.getUuid().encode(buf);
        buf.enc_ndr_short(this.binding.getMajor());
        buf.enc_ndr_short(this.binding.getMinor());
        DCERPC_UUID_SYNTAX_NDR.encode(buf);
        buf.enc_ndr_long(2); /* syntax version */
    }

    @Override

        buf.enc_ndr_short(0); /* context id */
        buf.enc_ndr_small(1); /* number of items */
        buf.enc_ndr_small(0); /* reserved */
        binding.uuid.encode(buf);
        buf.enc_ndr_short(binding.major);
        buf.enc_ndr_short(binding.minor);
        DCERPC_UUID_SYNTAX_NDR.encode(buf);
        buf.enc_ndr_long(2); /* syntax version */
    }

    @Override
    public void decode_out(final NdrBuffer buf) throws NdrException {

        this.fileName = new String(nameBytes, StandardCharsets.UTF_16LE);
        return bufferIndex - start;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.Encodable#encode(byte[], int)
     */
    @Override
    public int encode(final byte[] dst, int dstIndex) {
        final int start = dstIndex;
        dst[dstIndex] = (byte) (this.replaceIfExists ? 1 : 0);
        dstIndex += 8; // 7 Reserved

            final int _nodes = 6;
            final int _nodei = _src.index;
            _src.advance(1 * _nodes);

            if (this.node == null) {
                if (_nodes < 0 || _nodes > 0xFFFF) {
                    throw new NdrException(NdrException.INVALID_CONFORMANCE);
                }
                this.node = new byte[_nodes];
            }
            _src = _src.derive(_nodei);

**FastAPI** will make sure to read that data from the right place instead of JSON.

/// note | Technical Details

Data from forms is normally encoded using the "media type" `application/x-www-form-urlencoded` when it doesn't include files.

But when the form includes files, it is encoded as `multipart/form-data`. If you use `File`, **FastAPI** will know it has to get the files from the correct part of the body.