### Create the Tables { #create-the-tables }

We then add a function that uses `SQLModel.metadata.create_all(engine)` to **create the tables** for all the *table models*.

{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[21:22] hl[21:22] *}

### Create a Session Dependency { #create-a-session-dependency }

        HashBasedTable.create((Table<String, Integer, ? extends Character>) table);
    Table<String, Integer, C> reordered = create("foo", 3, 'c', "foo", 1, 'a', "bar", 1, 'b');
    Table<String, Integer, C> smaller = create("foo", 1, 'a', "bar", 1, 'b');
    Table<String, Integer, C> swapOuter = create("bar", 1, 'a', "foo", 1, 'b', "bar", 3, 'c');
    Table<String, Integer, C> swapValues = create("foo", 1, 'c', "bar", 1, 'b', "foo", 3, 'a');

  public static class ImmutableListOfGenerator extends TestStringListGenerator {
    @Override
    protected List<String> create(String[] elements) {
      return ImmutableList.copyOf(elements);
    }
  }

  public static class BuilderAddListGenerator extends TestStringListGenerator {
    @Override
    protected List<String> create(String[] elements) {
      ImmutableList.Builder<String> builder = ImmutableList.builder();

  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());

   */

  public void testSize() {
    int unused = create().size();
  }

  public void testIsEmpty() {
    boolean unused = create().isEmpty();
  }

  public void testRemove() {
    create().remove(null);
  }

  public void testClear() {
    create().clear();
  }

  public void testContainsKey() {
    boolean unused = create().containsKey(null);
  }

Let's make it give us the current user.

## Create a user model { #create-a-user-model }

First, let's create a Pydantic user model.

The same way we use Pydantic to declare bodies, we can use it anywhere else:

{* ../../docs_src/security/tutorial002_an_py310.py hl[5,12:6] *}

## Create a `get_current_user` dependency { #create-a-get-current-user-dependency }

Let's create a dependency `get_current_user`.

And an `APIRoute` subclass to use that custom request class.

### Create a custom `GzipRequest` class { #create-a-custom-gziprequest-class }

/// tip

This is a toy example to demonstrate how it works, if you need Gzip support, you can use the provided [`GzipMiddleware`](../advanced/middleware.md#gzipmiddleware).

///

  public void testComparator() {
    assertThat(create().comparator()).isNotNull();
  }

  public void testCeilingEntry() {
    assertThat(create().ceilingEntry("a")).isNull();
  }

  public void testCeilingKey() {
    assertThat(create().ceilingKey("a")).isNull();
  }

  public void testDescendingKeySet() {
    NavigableMap<String, Integer> map = create();

Swagger UI will handle it behind the scenes for you, but it needs this "redirect" helper.

///

### Create a *path operation* to test it { #create-a-path-operation-to-test-it }

Now, to be able to test that everything works, create a *path operation*:

{* ../../docs_src/custom_docs_ui/tutorial001_py310.py hl[36:38] *}

### Test it { #test-it }

///

### Create a callback `APIRouter` { #create-a-callback-apirouter }

First create a new `APIRouter` that will contain one or more callbacks.

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[1,23] *}

### Create the callback *path operation* { #create-the-callback-path-operation }

To create the callback *path operation* use the same `APIRouter` you created above.