```Python hl_lines="10"
{!> ../../docs_src/header_param_models/tutorial002.py!}
```

////

If a client tries to send some **extra headers**, they will receive an **error** response.

For example, if the client tries to send a `tool` header with a value of `plumbus`, they will receive an **error** response telling them that the header parameter `tool` is not allowed:

```json
{
    "detail": [
        {

    }
    filesToDelete.add(tempFile);
    return tempFile;
  }

  /**
   * Gets a temp dir for testing. The returned directory and all contents of it will be deleted in
   * the tear-down for this test. Subsequent invocations of this method will return the same
   * directory.
   */
  protected final File getTempDir() throws IOException {
    if (tempDir == null) {
      tempDir = createTempDir();
    }

 *   <li>It is easy for the user to ensure that listeners are never invoked while holding locks.
 * </ul>
 *
 * The last point is subtle. Often the observable object will be managing its own internal state
 * using a lock, however it is dangerous to dispatch listeners while holding a lock because they
 * might run on the {@code directExecutor()} or be otherwise re-entrant (call back into your

        } while( len > 0 && n == r );

        return (int)(fp - start);
    }
/**
 * This stream class is unbuffered. Therefore this method will always
 * return 0 for streams connected to regular files. However, a 
 * stream created from a Named Pipe this method will query the server using a
 * "peek named pipe" operation and return the number of available bytes
 * on the server.
 */

   * range sets a and b, the result of {@code a.add(range)} is that {@code a} will be the minimal
   * range set for which both {@code a.enclosesAll(b)} and {@code a.encloses(range)}.
   *
   * <p>Note that {@code range} will be {@linkplain Range#span(Range) coalesced} with any ranges in
   * the range set that are {@linkplain Range#isConnected(Range) connected} with it. Moreover, if

 * specified by the <tt>UniAddress</tt> parameter. If the credentials are
 * not accepted, an <tt>SmbAuthException</tt> will be thrown. If an error
 * occurs an <tt>SmbException</tt> will be thrown. If the credentials are
 * valid, the method will return without throwing an exception. See the
 * last <a href="../../../faq.html">FAQ</a> question.
 * <p>

     * legal NetBIOS name string is used a name query request will retreive
     * the IP, node type, and whether or not this NbtAddress represents a
     * group name. This degree of state can be obtained with a Name Query
     * Request or Node Status Request.
     * 
     * 3) All - The NbtAddress will be populated with all state such as mac

// "fifo_queue_enqueue_<tensor_id>", to be executed by this API call. It reads
// from a placeholder node "arg_tensor_enqueue_<tensor_id>".
//
// `tensor` is still owned by the caller. This call will be blocked if the queue
// has reached its capacity, and will be unblocked when the queued tensors again
// drop below the capacity due to dequeuing.
//
// Tensors are dequeued via the corresponding TF dequeue op.

I will show you some of the main concepts you should probably keep in mind when deploying a **FastAPI** application (although most of it applies to any other type of web application).

//     16 bytes of the encrypted ETag which will be a random
//     value.
//   - The object is a SSE-S3 encrypted single-part object.
//     In this case, the caller has to decrypt the ETag first
//     before calling Format.
//     S3 clients expect that the ETag of an SSE-S3 encrypted
//     single-part object is equal to the object's content MD5.
//     Formatting the SSE-S3 ETag before decryption will result