## Ask Questions { #ask-questions }

You can <a href="https://github.com/fastapi/fastapi/discussions/new?category=questions" class="external-link" target="_blank">create a new question</a> in the GitHub repository, for example to:

* Ask a **question** or ask about a **problem**.
* Suggest a new **feature**.

**Note**: if you do it, then I'm going to ask you to also help others. 😉

    * It contains the `username` and `password` sent.

{* ../../docs_src/security/tutorial006_an_py39.py hl[4,8,12] *}

When you try to open the URL for the first time (or click the "Execute" button in the docs) the browser will ask you for your username and password:

<img src="/img/tutorial/security/image12.png">

## Check the username { #check-the-username }

Here's a more complete example.

    }

    @Override
    public boolean hasNext() {
      return true; // pretend that you have more...
    }

    @Override
    public E next() {
      // ...but throw an unchecked exception when you ask for it.
      if (!iterator.hasNext()) {
        throw new ThrowsAtEndException();
      }
      return iterator.next();
    }

    @Override
    public void remove() {
      iterator.remove();

    assertEquals(Sets.<@Nullable String>newHashSet(null, "tree"), keySet.headSet("yahoo"));
    assertEquals(newHashSet("google"), keySet.tailSet("yahoo"));
    assertEquals(newHashSet("tree"), keySet.subSet("ask", "yahoo"));
  }

  @GwtIncompatible // SerializableTester
  public void testExplicitComparatorSerialization() {
    TreeMultimap<@Nullable String, @Nullable Integer> multimap = createPopulate();

    void testInitSecContextInitialToken() throws Exception {
        SpnegoContext ctx = newContext();

        // The initial token path should ask the mechanism for a zero-length optimistic token
        when(this.mechContext.getFlags()).thenReturn(0x1234);
        when(this.mechContext.initSecContext(any(byte[].class), eq(0), eq(0))).thenReturn(new byte[] { 0x01, 0x02 });

    @SuppressWarnings({ "rawtypes", "unchecked" })
    void testUnwrap() {
        SmbSessionImpl session = newSession();

        // Happy path: ask for SmbSession and SmbSessionInternal
        assertSame(session, session.unwrap(SmbSessionInternal.class));
        assertSame(session, session.unwrap(jcifs.SmbSession.class));

    //        MsrpcDfsRootEnum rpc;
    //        DcerpcHandle handle = null;
    //
    //        /* Procedure:
    //         * Lookup a DC in the target domain
    //         * Ask the DC for a referral for the domain (e.g. "\example.com")
    //         * Do NetrDfsEnumEx on the server returned in the referral to
    //         * get roots in target domain
    //         */
    //

On the other hand, if you have 2 servers and you are using **100% of their CPU and RAM**, at some point one process will ask for more memory, and the server will have to use the disk as "memory" (which can be thousands of times slower), or even **crash**. Or one process might need to do some computation and would have to wait until the CPU is free again.

  // Methods only in Iterables, not in Iterators

  /**
   * Determines if the given iterable contains no elements.
   *
   * <p>There is no precise {@link Iterator} equivalent to this method, since one can only ask an
   * iterator whether it has any elements <i>remaining</i> (which one does using {@link
   * Iterator#hasNext}).
   *
   * <p><b>{@code Stream} equivalent:</b> {@code !stream.findAny().isPresent()}
   *

  // Methods only in Iterables, not in Iterators

  /**
   * Determines if the given iterable contains no elements.
   *
   * <p>There is no precise {@link Iterator} equivalent to this method, since one can only ask an
   * iterator whether it has any elements <i>remaining</i> (which one does using {@link
   * Iterator#hasNext}).
   *
   * <p><b>{@code Stream} equivalent:</b> {@code !stream.findAny().isPresent()}
   *