MapDifference<Integer, String> original = Maps.difference(left, right);
    MapDifference<Integer, String> same = Maps.difference(left, right);
    MapDifference<Integer, String> reverse = Maps.difference(right, left);
    MapDifference<Integer, String> diff2 = Maps.difference(left, right2);

    new EqualsTester()
        .addEqualityGroup(original, same)

    MapDifference<Integer, String> original = Maps.difference(left, right);
    MapDifference<Integer, String> same = Maps.difference(left, right);
    MapDifference<Integer, String> reverse = Maps.difference(right, left);
    MapDifference<Integer, String> diff2 = Maps.difference(left, right2);

    new EqualsTester()
        .addEqualityGroup(original, same)

All the data conversion, validation, documentation, etc. will still work as normally.

That way, we can declare just the differences between the models (with plaintext `password`, with `hashed_password` and without password):

{* ../../docs_src/extra_models/tutorial002_py310.py hl[7,13:14,17:18,21:22] *}

## `Union` or `anyOf` { #union-or-anyof }

 * <h2>Relationship with Java compiler standard location</h2>
 * This enumeration is closely related to the {@link JavaFileManager.Location} enumerations.
 * A difference is that the latter enumerates input and output files, while {@code JavaPathType}
 * enumerates only input dependencies. Another difference is that {@code JavaPathType} contains
 * some enumeration values used only at runtime and therefore not available in {@code javax.tool},
 * such as agent paths.

* And it could also have a declaration of the response it should return, e.g. `response_model=InvoiceEventReceived`.

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[14:16,19:20,26:30] *}

There are 2 main differences from a normal *path operation*:

* It doesn't need to have any actual code, because your app will never call this code. It's only used to document the *external API*. So, the function could just have `pass`.

**FastAPI** has its own `HTTPException`.

And **FastAPI**'s `HTTPException` error class inherits from Starlette's `HTTPException` error class.

The only difference is that **FastAPI**'s `HTTPException` accepts any JSON-able data for the `detail` field, while Starlette's `HTTPException` only accepts strings for it.

So, you can keep raising **FastAPI**'s `HTTPException` as normally in your code.

    collected using form data (instead of JSON) and that it should have the specific
    fields `username` and `password`.

    All the initialization parameters are extracted from the request.

    The only difference between `OAuth2PasswordRequestFormStrict` and
    `OAuth2PasswordRequestForm` is that `OAuth2PasswordRequestFormStrict` requires the
    client to send the form field `grant_type` with the value `"password"`, which

    // array of indexes to be calculated is modified between the calls to indexes and compute: since
    // the contract is that it is snapshotted, this shouldn't make any difference to the result.
    int[] indexes = {0, 10, 5, 1, 8, 10};
    ScaleAndIndexes intermediate = Quantiles.scale(10).indexes(indexes);
    indexes[0] = 3;
    assertThat(intermediate.compute(SIXTEEN_SQUARES_DOUBLES))

    // array of indexes to be calculated is modified between the calls to indexes and compute: since
    // the contract is that it is snapshotted, this shouldn't make any difference to the result.
    int[] indexes = {0, 10, 5, 1, 8, 10};
    ScaleAndIndexes intermediate = Quantiles.scale(10).indexes(indexes);
    indexes[0] = 3;
    assertThat(intermediate.compute(SIXTEEN_SQUARES_DOUBLES))

---

You could also define it as a normal function instead of `async def`:

{* ../../docs_src/first_steps/tutorial003_py39.py hl[7] *}

/// note

If you don't know the difference, check the [Async: *"In a hurry?"*](../async.md#in-a-hurry){.internal-link target=_blank}.

///

### Step 5: return the content { #step-5-return-the-content }