assertTrue(ArbitraryInstances.get(ConcurrentMap.class).isEmpty());
    assertTrue(ArbitraryInstances.get(ConcurrentNavigableMap.class).isEmpty());
    ArbitraryInstances.get(Executor.class).execute(ArbitraryInstances.get(Runnable.class));
    assertThat(ArbitraryInstances.get(ThreadFactory.class)).isNotNull();
    assertFreshInstanceReturned(
        BlockingQueue.class,
        BlockingDeque.class,

      TimeUnit unit)
      throws InterruptedException {
    Preconditions.checkNotNull(buffer);
    /*
     * This code performs one System.nanoTime() more than necessary, and in return, the time to
     * execute Queue#drainTo is not added *on top* of waiting for the timeout (which could make
     * the timeout arbitrarily inaccurate, given a queue that is slow to drain).
     */

* PostgreSQL
* MySQL
* SQLite
* Oracle
* Microsoft SQL Server, etc.

Neste exemplo, usaremos **SQLite**, porque ele usa um único arquivo e o Python tem suporte integrado. Assim, você pode copiar este exemplo e executá-lo como está.

Mais tarde, para sua aplicação em produção, você pode querer usar um servidor de banco de dados como o **PostgreSQL**.

/// tip | Dica

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