List<E> contents = copyToList(getMultiset());
    assertFalse(getMultiset().retainAll(singleton(e0())));
    expectContents(contents);
  }

  /**
   * Returns {@link Method} instances for the remove tests that assume multisets support duplicates
   * so that the test of {@code Multisets.forSet()} can suppress them.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection

    List<E> contents = copyToList(getMultiset());
    assertFalse(getMultiset().retainAll(singleton(e0())));
    expectContents(contents);
  }

  /**
   * Returns {@link Method} instances for the remove tests that assume multisets support duplicates
   * so that the test of {@code Multisets.forSet()} can suppress them.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection

    }

    @Override
    public Map<String, Collection<Integer>> create(Object... elements) {
      ImmutableMap.Builder<String, Integer> builder = ImmutableMap.builder();
      // assumes that each set is a singleton or less (as is done for the samples)
      for (Object elem : elements) {
        @SuppressWarnings("unchecked") // safe by generator contract

  public void testElementSetClear() {
    getMultiset().elementSet().clear();
    assertEmpty(getMultiset());
  }

  /**
   * Returns {@link Method} instances for the read tests that assume multisets support duplicates so
   * that the test of {@code Multisets.forSet()} can suppress them.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection

public final class NtlmChallenge implements Serializable {

    /**
     * The NTLM challenge bytes received from the server.
     */
    public byte[] challenge;
    /**
     * The domain controller address that issued the challenge.
     */
    public UniAddress dc;

    NtlmChallenge(final byte[] challenge, final UniAddress dc) {
        this.challenge = challenge;
        this.dc = dc;
    }

    @Override

 * {@link #unmodifiableKeySet()}. By design, the cache is cleared when this structure is mutated. If
 * this structure is never mutated, it provides a thread-safe view of the backing map.
 *
 * <p>The {@link MapIteratorCache} assumes ownership of the backing map, and cannot guarantee
 * correctness in the face of external mutations to the backing map. As such, it is <b>strongly</b>

   colleagues before taking action. For example, changes to code, infrastructure, policy, and
   documentation may negatively impact others.

 * **Be respectful**: We expect people to work together to resolve conflict, assume good intentions,
   and act with empathy. Do not turn disagreements into personal attacks.

 * **Be collaborative**: Collaboration reduces redundancy and improves the quality of our work. We

</div>

This means that it will **always have a value**, it's just that sometimes the value could be `None` (or `null` in JSON).

That means that, clients using your API don't have to check if the value exists or not, they can **assume the field will always be there**, but just that in some cases it will have the default value of `None`.

The way to describe this in OpenAPI, is to mark that field as **required**, because it will always be there.

		lrw.bytesWritten += int(n)
		return n, err
	}
	return 0, ErrNotImplemented
}

func (lrw *ResponseRecorder) Write(p []byte) (int, error) {
	if !lrw.headersLogged {
		// We assume the response code to be '200 OK' when WriteHeader() is not called,
		// that way following Golang HTTP response behavior.
		lrw.WriteHeader(http.StatusOK)
	}
	n, err := lrw.ResponseWriter.Write(p)
	lrw.bytesWritten += n

Aún podrías usar la mayoría de las funcionalidades en **FastAPI** con el conocimiento del [Tutorial - Guía del usuario](../tutorial/index.md){.internal-link target=_blank} principal.