return new RequestBody() {
        @Override public MediaType contentType() {
          return body.contentType();
        }

        @Override public long contentLength() {
          return -1; // We don't know the compressed length in advance!
        }

        @Override public void writeTo(BufferedSink sink) throws IOException {
          BufferedSink gzipSink = Okio.buffer(new GzipSink(sink));

    assertUnescaped(e, '!');
    assertUnescaped(e, '\'');
    assertUnescaped(e, '(');
    assertUnescaped(e, ')');
    assertUnescaped(e, '~');
    assertUnescaped(e, ':');
    assertUnescaped(e, '@');

    // Don't use plus for spaces
    assertEscaping(e, "%20", ' ');

    assertEquals("safe%20with%20spaces", e.escape("safe with spaces"));
    assertEquals("******@****.***", e.escape("******@****.***"));
  }

         * as a special case (which it is).
         */
        if (errcode == 0) {
            return "NT_STATUS_SUCCESS";
        }
        if(( errcode & 0xC0000000 ) == 0xC0000000 ) {
            int min = 1; /* Don't include NT_STATUS_SUCCESS */
            int max = NT_STATUS_CODES.length - 1;

            while( max >= min ) {
                int mid = (min + max) / 2;

                if( errcode > NT_STATUS_CODES[mid] ) {

///

## Shortcut to remember the names

Let's see the previous example again:

{* ../../docs_src/response_status_code/tutorial001.py hl[6] *}

`201` is the status code for "Created".

But you don't have to memorize what each of these codes mean.

You can use the convenience variables from `fastapi.status`.

{* ../../docs_src/response_status_code/tutorial002.py hl[1,6] *}

/// tip

Don't worry if some of these items about **containers**, Docker, or Kubernetes don't make a lot of sense yet.

I'll tell you more about container images, Docker, Kubernetes, etc. in a future chapter: [FastAPI in Containers - Docker](docker.md){.internal-link target=_blank}.

		// When we serialize we don't care if it was trailing.
		c.Type ^= ChecksumTrailing
	}
	if len(crc) != c.Type.RawByteLen() {
		return b
	}
	b = append(b, tmp[:n]...)
	b = append(b, crc...)
	if c.Type.Is(ChecksumMultipart) {
		var checksums int
		if c.WantParts > 0 && !c.Type.Is(ChecksumIncludesMultipart) {
			checksums = c.WantParts
		}
		// Ensure we don't divide by 0:

			return err
		}
		boff += consumed
		if len(name) == 0 || bytes.Equal(name, []byte{'.'}) || bytes.Equal(name, []byte{'.', '.'}) {
			continue
		}

		// Fallback for filesystems (like old XFS) that don't
		// support Dirent.Type and have DT_UNKNOWN (0) there
		// instead.
		if typ == unexpectedFileMode || typ&os.ModeSymlink == os.ModeSymlink {
			fi, err := Stat(pathJoin(dirPath, string(name)))
			if err != nil {

    } else if (isDone()) {
      addDoneString(builder);
    } else {
      String pendingDescription;
      try {
        pendingDescription = pendingToString();
      } catch (RuntimeException e) {
        // Don't call getMessage or toString() on the exception, in case the exception thrown by the
        // subclass is implemented with bugs similar to the subclass.

# About HTTPS

It is easy to assume that HTTPS is something that is just "enabled" or not.

But it is way more complex than that.

/// tip

If you are in a hurry or don't care, continue with the next sections for step by step instructions to set everything up with different techniques.

///

  }

  /*
   * Whenever an implementation uses `instanceof` on a parameter instance, the test has to know that
   * (so much for "black box") and try instances that both do and don't pass the check. The "don't"
   * half of that is more awkward to arrange...
   */
  private static <T> Iterable<T> iterable(final Collection<T> collection) {
    // return collection::iterator;
    return new Iterable<T>() {