You declare the dependency as the type of the parameter, and you use `Depends()` without any parameter, instead of having to write the full class *again* inside of `Depends(CommonQueryParams)`.

The same example would then look like:

=== "Python 3.10+"

    ```Python hl_lines="19"
    {!> ../../../docs_src/dependencies/tutorial004_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="19"

    ```Python hl_lines="20-27"
    {!> ../../../docs_src/schema_extra_example/tutorial003.py!}
    ```

### Example in the docs UI

With any of the methods above it would look like this in the `/docs`:

<img src="/img/tutorial/body-fields/image01.png">

### `Body` with multiple `examples`

You can of course also pass multiple `examples`:

=== "Python 3.10+"

For example, if some code at some point in the middle, in another dependency or in a *path operation*, made a database transaction "rollback" or create any other error, you will receive the exception in your dependency.

So, you can look for that specific exception inside the dependency with `except SomeException`.

In the same way, you can use `finally` to make sure the exit steps are executed, no matter if there was an exception or not.

This could be especially useful during testing, as it's very easy to override a dependency with your own custom settings.

### The config file

Coming from the previous example, your `config.py` file could look like:

```Python hl_lines="10"
{!../../../docs_src/settings/app02/config.py!}
```

Notice that now we don't create a default instance `settings = Settings()`.

### The main app file

It will look like this:

<img src="/img/tutorial/sql-databases/image02.png">

You would of course use the same ideas you read in [About FastAPI versions](versions.md){.internal-link target=_blank} to set the ranges of versions.

For example, your `requirements.txt` could look like:

```
fastapi>=0.112.0,<0.113.0
pydantic>=2.7.0,<3.0.0
```

And you would normally install those package dependencies with `pip`, for example:

<div class="termy">

```console

Но внутреннее устройство **конкурентности** и **параллелизма** довольно разное.

Чтобы это понять, представьте такую картину:

### Конкурентные бургеры

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