}

  public Test testsForEmptySet() {
    return SetTestSuiteBuilder.using(
            new TestStringSetGenerator() {
              @Override
              public Set<String> create(String[] elements) {
                return Collections.emptySet();
              }
            })
        .named("emptySet")
        .withFeatures(CollectionFeature.SERIALIZABLE, CollectionSize.ZERO)

    SettableFuture<String> future = SettableFuture.create();
    SettableFuture<String> nested = SettableFuture.create();
    assertTrue(future.setFuture(nested));
    // Later attempts to set the future should return false.
    assertFalse(future.set("x"));
    assertFalse(future.setException(new Exception("bar")));
    assertFalse(future.setFuture(SettableFuture.<String>create()));
    // Check that the future has been set properly.

    SettableFuture<String> future = SettableFuture.create();
    SettableFuture<String> nested = SettableFuture.create();
    assertTrue(future.setFuture(nested));
    // Later attempts to set the future should return false.
    assertFalse(future.set("x"));
    assertFalse(future.setException(new Exception("bar")));
    assertFalse(future.setFuture(SettableFuture.<String>create()));
    // Check that the future has been set properly.

Here, this section would run directly, right before starting your **FastAPI** application.

* Create an `engine`.
* Create all the tables from the `metadata` object.

```Python hl_lines="25-28"
{!../../../docs_src/async_sql_databases/tutorial001.py!}
```

## Create models

Create Pydantic models for:

* Notes to be created (`NoteIn`).

    BiPredicate<Multimap<?, ?>, Multimap<?, ?>> equivalence =
        Equivalence.equals()
            .onResultOf((Multimap<?, ?> mm) -> ImmutableList.copyOf(mm.asMap().entrySet()))
            .and(Equivalence.equals());
    TreeMultimap<String, Integer> empty = TreeMultimap.create();
    TreeMultimap<String, Integer> filled = TreeMultimap.create();
    filled.put("a", 1);

  }

  public Test testsForCheckedNavigableSet() {
    return SortedSetTestSuiteBuilder.using(
            new TestStringSortedSetGenerator() {
              @Override
              public NavigableSet<String> create(String[] elements) {
                NavigableSet<String> innerSet = new TreeSet<>();
                Collections.addAll(innerSet, elements);
                return Collections.checkedNavigableSet(innerSet, String.class);

  protected TreeBasedTable<String, Integer, Character> create(@Nullable Object... data) {
    TreeBasedTable<String, Integer, Character> table = TreeBasedTable.create();
    table.put("foo", 4, 'a');
    table.put("cat", 1, 'b');
    table.clear();
    populate(table, data);
    return table;
  }

  public void testCreateExplicitComparators() {
    table = TreeBasedTable.create(Collections.reverseOrder(), Ordering.usingToString());

## Create the database

Because now we are going to use a new database in a new file, we need to make sure we create the database with:

```Python
Base.metadata.create_all(bind=engine)
```

That is normally called in `main.py`, but the line in `main.py` uses the database file `sql_app.db`, and we need to make sure we create `test.db` for the tests.

        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/files/": {
                "post": {
                    "summary": "Create File",
                    "operationId": "create_file_files__post",
                    "requestBody": {
                        "content": {
                            "multipart/form-data": {
                                "schema": IsDict(

        "openapi": "3.1.0",
        "info": {"title": "FastAPI", "version": "0.1.0"},
        "paths": {
            "/files/": {
                "post": {
                    "summary": "Create File",
                    "operationId": "create_file_files__post",
                    "requestBody": {
                        "content": {
                            "multipart/form-data": {
                                "schema": IsDict(