* @author Joshua O'Madadhain
 * @param <N> The most general node type this builder will support. This is normally {@code Object}
 *     unless it is constrained by using a method like {@link #nodeOrder}, or the builder is
 *     constructed based on an existing {@code Network} using {@link #from(Network)}.
 * @param <E> The most general edge type this builder will support. This is normally {@code Object}

	} else {
		if !lm.isWriteLock {
			lm.ref++
			locked = true
		}
	}

	return locked
}

const (
	lockRetryInterval = 50 * time.Millisecond
)

// lockLoop will acquire either a read or a write lock
//
// The call will block until the lock is granted using a built-in
// timing randomized back-off algorithm to try again until successful

    'email': '******@****.***',
    'full_name': None,
}
```

#### Unwrapping a `dict`

If we take a `dict` like `user_dict` and pass it to a function (or class) with `**user_dict`, Python will "unwrap" it. It will pass the keys and values of the `user_dict` directly as key-value arguments.

So, continuing with the `user_dict` from above, writing:

```Python
UserInDB(**user_dict)
```

 * Open the Named Pipe foo for reading and writing. The pipe will behave like the <code>CallNamedPipe</code> interface.
 * </td></tr>
 * <tr><td width="20%"><pre>
 * new SmbNamedPipe( "smb1://server/IPC$/foo",
 *         SmbNamedPipe.PIPE_TYPE_RDWR |
 *         SmbNamedPipe.PIPE_TYPE_TRANSACT );
 * </pre></td><td>
 * Open the Named Pipe foo for reading and writing. The pipe will behave like the <code>TransactNamedPipe</code> interface.

```Python hl_lines="3-16  18"
{!../../docs_src/metadata/tutorial004.py!}
```

Notice that you can use Markdown inside of the descriptions, for example "login" will be shown in bold (**login**) and "fancy" will be shown in italics (_fancy_).

/// tip

You don't have to add metadata for all the tags that you use.

///

### Use your tags

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

## Feature implementation

Release managers will continue to have a final say in what gets merged or not, unless directed by the TOC. See the next
section if the implementation is done, but a bug is being addressed.

* Any code that changes feature functionality must be done within 2 weeks of the release branch cutting. Even then it is
 at the discretion of the release managers if PRs will be accepted and merged into the release branch.

///

It will:

* Return that status code in the response.
* Document it as such in the OpenAPI schema (and so, in the user interfaces):

<img src="/img/tutorial/response-status-code/image01.png">

/// note

Some response codes (see the next section) indicate that the response does not have a body.

FastAPI knows this, and will produce OpenAPI docs that state there is no response body.

   * except {@link Object#equals}, {@link Object#hashCode} and {@link Object#toString}. The result
   * will be returned as the proxied method's return value.
   *
   * <p>Unlike {@link #invoke}, {@code args} will never be null. When the method has no parameter,
   * an empty array is passed in.
   */
  @CheckForNull

	authFields := strings.Split(r.Header.Get(xhttp.Authorization), " ")
	if len(authFields) != 2 {
		return auth.Credentials{}, false, ErrMissingFields
	}

	// Then will be splitting on ":", this will separate `AWSAccessKeyId` and `Signature` string.
	keySignFields := strings.Split(strings.TrimSpace(authFields[1]), ":")
	if len(keySignFields) != 2 {
		return auth.Credentials{}, false, ErrMissingFields
	}