try {
            // Measure timing for differences at different positions
            long timeStart = measureEqualsTime(baseAuth, startAuth, TIMING_ITERATIONS);
            long timeMiddle = measureEqualsTime(baseAuth, middleAuth, TIMING_ITERATIONS);
            long timeEnd = measureEqualsTime(baseAuth, endAuth, TIMING_ITERATIONS);

            // Calculate relative timing differences

Also, the best approach was to use already existing standards.

So, before even starting to code **FastAPI**, I spent several months studying the specs for OpenAPI, JSON Schema, OAuth2, etc. Understanding their relationship, overlap, and differences.

## Design { #design }

Then I spent some time designing the developer "API" I wanted to have as a user (as a developer using FastAPI).

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 }

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

{* ../../docs_src/openapi_callbacks/tutorial001.py hl[16:18,21:22,28:32] *}

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`.

{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[1:11] hl[7:11] *}

The `Hero` class is very similar to a Pydantic model (in fact, underneath, it actually *is a Pydantic model*).

There are a few differences:

* `table=True` tells SQLModel that this is a *table model*, it should represent a **table** in the SQL database, it's not just a *data model* (as would be any other regular Pydantic class).

    /**
     * Performs constant-time comparison of two char arrays to prevent timing attacks.
     * This method always compares the full length of both arrays, regardless of when
     * differences are found, making the execution time independent of the position
     * of differing characters.
     *
     * @param a first char array to compare
     * @param b second char array to compare

> Vous devez nettoyer une grande et sale maison.

*Oui, c'est toute l'histoire*.

---

Il n'y a plus d'attente 🕙 nulle part, juste beaucoup de travail à effectuer, dans différentes pièces de la maison.

Vous pourriez diviser en différentes sections comme avec les burgers, d'abord le salon, puis la cuisine, etc. Mais vous n'attendez 🕙 rien, vous ne faites que nettoyer et nettoyer, la séparation en sections ne changerait rien au final.

Neste caso, ele requer o escopo `me` (poderia requerer mais de um escopo).

/// note | Nota

Você não necessariamente precisa adicionar diferentes escopos em diferentes lugares.

Nós estamos fazendo isso aqui para demonstrar como o **FastAPI** lida com escopos declarados em diferentes níveis.

///

{* ../../docs_src/security/tutorial005_an_py310.py hl[5,140,171] *}

/// info | Informações Técnicas

En este caso, requiere el scope `me` (podría requerir más de un scope).

/// note | Nota

No necesariamente necesitas añadir diferentes scopes en diferentes lugares.

Lo estamos haciendo aquí para demostrar cómo **FastAPI** maneja scopes declarados en diferentes niveles.

///

{* ../../docs_src/security/tutorial005_an_py310.py hl[5,140,171] *}

/// info | Información Técnica

**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.