But all this functionality of using asynchronous code with `async` and `await` is many times summarized as using "coroutines". It is comparable to the main key feature of Go, the "Goroutines".

## Conclusion

Because it's a Python exception, you don't `return` it, you `raise` it.

It used custom types in its declarations instead of standard Python types, but it was still a huge step forward.

It also was one of the first frameworks to generate a custom schema declaring the whole API in JSON.

It was not based on a standard like OpenAPI and JSON Schema. So it wouldn't be straightforward to integrate it with other tools, like Swagger UI. But again, it was a very innovative idea.

# Deployment

Deploying a **FastAPI** application is relatively easy.

## What Does Deployment Mean

To **deploy** an application means to perform the necessary steps to make it **available to the users**.

For a **web API**, it normally involves putting it in a **remote machine**, with a **server program** that provides good performance, stability, etc, so that your **users** can **access** the application efficiently and without interruptions or problems.

    Iterator<Integer> it = mmHeap.iterator();
    assertEquals((Integer) 1, it.next());
    assertEquals((Integer) 20, it.next());
    assertEquals((Integer) 100, it.next());
    assertEquals((Integer) 2, it.next());
    it.remove();
    assertFalse(mmHeap.contains(2));
    assertTrue(it.hasNext());
    assertEquals((Integer) 3, it.next());
    assertTrue(it.hasNext());

    This defines the name of the query parameter that should be provided in the request
    with the API key and integrates that into the OpenAPI documentation. It extracts
    the key value sent in the query parameter automatically and provides it as the
    dependency result. But it doesn't define how to send that API key to the client.

    ## Usage

    Create an instance object and use that object as the dependency in `Depends()`.

    this?.takeIf { it.isNotEmpty() }
        ?.joinToString(separator = ", ", prefix = "<", postfix = ">", transform = transform)
        ?: ""


private
val ApiTypeUsage.isGroovyNamedArgumentMap
    get() = isMap && (
        typeArguments.all { it.isAny }
            || typeArguments.all { it.isStarProjectionTypeUsage }

    assertThat(events2).isEqualTo(expectedEvents2)
  }

  private fun isConnectionEvent(it: CallEvent?) =
    it is CallStart ||
      it is CallEnd ||
      it is ConnectStart ||
      it is ConnectEnd ||
      it is ConnectionAcquired ||
      it is ConnectionReleased ||
      it is Canceled ||
      it is RequestFailed ||
      it is ResponseFailed

  private fun sleep(delayMillis: Int) {
    try {

        final LineIterator it = new LineIterator(reader);
        assertThat(it.hasNext(), is(true));
        assertThat(it.next(), is("aaa"));
        assertThat(it.hasNext(), is(true));
        assertThat(it.next(), is("bbb"));
        assertThat(it.hasNext(), is(true));
        assertThat(it.next(), is("ccc"));
        assertThat(it.hasNext(), is(not(true)));
    }

    /**

  /**
   * This is mutable and order matters. By default, it contains [IPv4, IPv6]. Tests may manipulate
   * it to prefer IPv6.
   */
  private var dnsResults = listOf<InetAddress>()

  @BeforeEach
  internal fun setUp() {
    val inetAddresses = InetAddress.getAllByName("localhost")
    localhostIpv4 = inetAddresses.firstOrNull { it is Inet4Address }
      ?: throw TestAbortedException()