public void testReturning() throws Exception {
    assertThat(Callables.returning(null).call()).isNull();

    Object value = new Object();
    Callable<Object> callable = Callables.returning(value);
    assertThat(callable.call()).isEqualTo(value);
    // Expect the same value on subsequent calls
    assertThat(callable.call()).isEqualTo(value);
  }

  @J2ktIncompatible
  @GwtIncompatible

  public void testReturning() throws Exception {
    assertThat(Callables.returning(null).call()).isNull();

    Object value = new Object();
    Callable<Object> callable = Callables.returning(value);
    assertThat(callable.call()).isEqualTo(value);
    // Expect the same value on subsequent calls
    assertThat(callable.call()).isEqualTo(value);
  }

  @J2ktIncompatible
  @GwtIncompatible

    TestExecutor(MockExecutor mock) {
      super(mock);
    }

    @Override
    protected <T> Callable<T> wrapTask(Callable<T> callable) {
      return new WrappedCallable<T>(callable);
    }

    @Override
    protected Runnable wrapTask(Runnable command) {
      return new WrappedRunnable(command);
    }
  }

    TestExecutor(MockExecutor mock) {
      super(mock);
    }

    @Override
    protected <T> Callable<T> wrapTask(Callable<T> callable) {
      return new WrappedCallable<T>(callable);
    }

    @Override
    protected Runnable wrapTask(Runnable command) {
      return new WrappedRunnable(command);
    }
  }

  /**
   * Creates a {@code ListenableFutureTask} that will upon running, execute the given {@code
   * Callable}.
   *
   * @param callable the callable task
   * @since 10.0
   */
  public static <V extends @Nullable Object> ListenableFutureTask<V> create(Callable<V> callable) {
    return new ListenableFutureTask<>(callable);
  }

  /**
   * Creates a {@code ListenableFutureTask} that will upon running, execute the given {@code

    }
  }

  private static List<Callable<String>> createTasks(int n) {
    List<Callable<String>> callables = new ArrayList<>();
    for (int i = 0; i < n; i++) {
      callables.add(Callables.returning(RESULT_VALUE + i));
    }
    return callables;
  }

  private static final class WrappedCallable<T> implements Callable<T> {
    private final Callable<T> delegate;

public final class ListeningExecutorServiceTest extends TestCase {

  private Collection<? extends Callable<?>> recordedTasks;
  private long recordedTimeout;
  private TimeUnit recordedTimeUnit;

  private final ListeningExecutorService executorService = new FakeExecutorService();

  public void testInvokeAny() throws Exception {
    Set<Callable<String>> tasks = Collections.singleton(() -> "invokeAny");

그리고 `fluffy`를 만들기 위해 `Cat`을 "호출"하고 있습니다.

따라서 파이썬 클래스도 **호출 가능(callable)**합니다.

그러면 **FastAPI**에서는 파이썬 클래스를 의존성으로 사용할 수 있습니다.

FastAPI가 실제로 확인하는 것은 그것이 "호출 가능(callable)"(함수, 클래스, 또는 다른 무엇이든)한지와 정의된 매개변수들입니다.

**FastAPI**에서 "호출 가능(callable)"한 것을 의존성으로 넘기면, 그 "호출 가능(callable)"한 것의 매개변수들을 분석하고 *경로 처리 함수*의 매개변수와 동일한 방식으로 처리합니다. 하위 의존성도 포함해서요.

이것은 매개변수가 전혀 없는 callable에도 적용됩니다. 매개변수가 없는 *경로 처리 함수*에 적용되는 것과 동일합니다.

import types
from collections.abc import Callable
from enum import Enum
from typing import Any, TypeVar, Union

from pydantic import BaseModel
from pydantic.main import IncEx as IncEx

DecoratedCallable = TypeVar("DecoratedCallable", bound=Callable[..., Any])
UnionType = getattr(types, "UnionType", Union)
ModelNameMap = dict[type[BaseModel] | type[Enum], str]

    set: list,
    UUID: str,
    Url: str,
    AnyUrl: str,
}


def generate_encoders_by_class_tuples(
    type_encoder_map: dict[Any, Callable[[Any], Any]],
) -> dict[Callable[[Any], Any], tuple[Any, ...]]:
    encoders_by_class_tuples: dict[Callable[[Any], Any], tuple[Any, ...]] = defaultdict(
        tuple
    )
    for type_, encoder in type_encoder_map.items():