* `Field(primary_key=True)` для SQLModel означает, что поле `id` является первичным ключом в таблице базы данных (вы можете подробнее узнать о первичных ключах баз данных в документации по SQLModel).

    Тип `int | None` сигнализирует для SQLModel, что столбец таблицы базы данных должен иметь тип `INTEGER`, или иметь пустое значение  `NULL`.

    void awaitWaiting() {
      while (!isBlocked()) {
        if (getState() == State.TERMINATED) {
          throw new RuntimeException("Thread exited");
        }
        Thread.yield();
      }
    }

    private boolean isBlocked() {
      return getState() == Thread.State.WAITING && LockSupport.getBlocker(this) == future;
    }
  }

     * 10^floor(log10(x)).
     */

    if (approxCmp > 0) {
      /*
       * The code is written so that even completely incorrect approximations will still yield the
       * correct answer eventually, but in practice this branch should almost never be entered, and
       * even then the loop should not run more than once.
       */
      do {
        approxLog10--;

* `Field(primary_key=True)` le dice a SQLModel que `id` es la **clave primaria** en la base de datos SQL (puedes aprender más sobre claves primarias de SQL en la documentación de SQLModel).

    Al tener el tipo como `int | None`, SQLModel sabrá que esta columna debe ser un `INTEGER` en la base de datos SQL y que debe ser `NULLABLE`.

                }
              });
      expectedKeys.add(s);
    }

    computationLatch.countDown();
    // let some computations complete
    while (computedCount.get() < nThreads) {
      Thread.yield();
    }
    cache.invalidateAll();
    tasksFinished.await();

    // Check all of the removal notifications we received: they should have had correctly-associated

                }
              });
      expectedKeys.add(s);
    }

    computationLatch.countDown();
    // let some computations complete
    while (computedCount.get() < nThreads) {
      Thread.yield();
    }
    cache.invalidateAll();
    tasksFinished.await();

    // Check all of the removal notifications we received: they should have had correctly-associated

   *
   *  * A `SYN_RESET` frame abnormally terminates the stream.
   *  * Both input and output streams have transmitted all data and headers.
   *
   * Note that the input stream may continue to yield data even after a stream reports itself as
   * not open. This is because input data is buffered.
   */
  val isOpen: Boolean
    get() {
      withLock {
        if (errorCode != null) {
          return false

    sink.writeUtf8(content)
    sink.close()
  }

  /**
   * @param delta the offset from the current date to use. Negative values yield dates in the past;
   * positive values yield dates in the future.
   */
  private fun formatDate(
    delta: Long,
    timeUnit: TimeUnit,
  ): String = formatDate(Date(System.currentTimeMillis() + timeUnit.toMillis(delta)))

   * {@link Predicate#apply}), the returned predicate may not be <i>consistent with equals</i>. For
   * example, {@code instanceOf(ArrayList.class)} will yield different results for the two equal
   * instances {@code Lists.newArrayList(1)} and {@code Arrays.asList(1)}.
   *
   * <p><b>Discouraged:</b> Prefer using {@code clazz::isInstance} or {@code x -> x instanceof

* `Field(primary_key=True)`는 SQLModel에 `id`가 SQL 데이터베이스의 **기본 키**임을 알려줍니다 (SQL 기본 키에 대한 자세한 내용은 SQLModel 문서를 참고하세요).

    `int | None` 유형으로 설정하면, SQLModel은 해당 열이 SQL 데이터베이스에서 `INTEGER` 유형이며 `NULLABLE` 값이어야 한다는 것을 알 수 있습니다.

* `Field(index=True)`는 SQLModel에 해당 열에 대해 **SQL 인덱스**를 생성하도록 지시합니다. 이를 통해 데이터베이스에서 이 열으로 필터링된 데이터를 읽을 때 더 빠르게 조회할 수 있습니다.