因为默认值是 `None`， FastAPI 会把 `q` 当作可选参数。

FastAPI 不使用 `Optional[str]` 中的 `Optional`， 但 `Optional` 可以让编辑器提供更好的支持，并检测错误。

///

## 不使用 Pydantic

O corpo da **requisição** é a informação enviada pelo cliente para sua API. O corpo da **resposta** é a informação que sua API envia para o cliente.

Sua API quase sempre irá enviar um corpo na **resposta**. Mas os clientes não necessariamente precisam enviar um corpo em toda **requisição**.

/**
 * Plexus invoker implementation, that boots up Plexus DI container. This class expects fully setup ClassWorld via constructor.
 *
 * @param <O> the options type
 * @param <R> the request type
 * @param <C> the context type
 */
public abstract class LookupInvoker<
                O extends Options, R extends InvokerRequest<O>, C extends LookupInvoker.LookupInvokerContext<O, R, C>>

                        logger.info("Could not kill the subprocess.", e);
                    }
                }
            }
        }

        /**
         * @param finished
         *            The finished to set.
         */
        public void setFinished(final boolean finished) {
            this.finished = finished;
        }

        /**

              .append(" ")
              .append(method.getName())
              .append("(");
      String sep = "";
      for (Class<?> param : method.getParameterTypes()) {
        signature.append(sep).append(typeName(param));
        sep = ", ";
      }
      methods.add(signature.append(")").toString());
    }
    return methods.build();
  }

   * thereof.
   *
   * @param formal The type whose type variables or itself is mapped to other type(s). It's almost
   *     always a bug if {@code formal} isn't a type variable and contains no type variable. Make
   *     sure you are passing the two parameters in the right order.
   * @param actual The type that the formal type variable(s) are mapped to. It can be or contain yet

              .append(" ")
              .append(method.getName())
              .append("(");
      String sep = "";
      for (Class<?> param : method.getParameterTypes()) {
        signature.append(sep).append(typeName(param));
        sep = ", ";
      }
      methods.add(signature.append(")").toString());
    }
    return methods.build();
  }

/**
 * Tests representing the contract of {@link Map}. Concrete subclasses of this base class test
 * conformance of concrete {@link Map} subclasses to that contract.
 *
 * @param <K> the type of keys used by the maps under test
 * @param <V> the type of mapped values used the maps under test
 * @author George van den Driessche
 */
// TODO: Descriptive assertion messages, with hints as to probable fixes.

 *       for implementors</a>
 * </ul>
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @param <N> Node parameter type
 * @param <V> Value parameter type
 * @since 20.0
 */
@Beta
@ElementTypesAreNonnullByDefault
public interface ValueGraph<N, V> extends BaseGraph<N> {
  //
  // ValueGraph-level accessors
  //

    Invokable<T, ?> invokable = new TypeToken<T>(getClass()) {}.method(setMethod);
    ImmutableList<Parameter> params = invokable.getParameters();
    assertEquals(2, params.size());
    assertEquals(TypeToken.of(int.class), params.get(0).getType());
    assertEquals(TypeToken.of(String.class), params.get(1).getType());
  }

  public void testMethod_equals() throws NoSuchMethodException {