List<Integer> bazList = filtered.get("baz");
    assertThat(bazList).isEmpty();
    assertThrows(IllegalArgumentException.class, () -> bazList.add(5));
    assertThrows(IllegalArgumentException.class, () -> bazList.add(0, 6));
    assertThrows(IllegalArgumentException.class, () -> bazList.addAll(ImmutableList.of(7, 8)));
    assertThrows(IllegalArgumentException.class, () -> bazList.addAll(0, ImmutableList.of(9, 10)));
  }

* The alternative documentation will also reflect the new query parameter and body:

![ReDoc](https://fastapi.tiangolo.com/img/index/index-06-redoc-02.png)

### Recap

In summary, you declare **once** the types of parameters, body, etc. as function parameters.

You do that with standard modern Python types.