So, in our case, if we set the Peewee state variable (with a default `dict`) in the `async` dependency, all the rest of the internal code in our app will see this value and will be able to reuse it for the whole request.

And the context variable would be set again for the next request, even if they are concurrent.

### Set database state in the dependency `get_db()`

    Note over client,tasks: Can raise exception for dependency, handled after response is sent
    Note over client,operation: Can raise HTTPException and can change the response
    client ->> dep: Start request
    Note over dep: Run code up to yield
    opt raise
        dep -->> handler: Raise HTTPException
        handler -->> client: HTTP error response
        dep -->> dep: Raise other exception
    end

    Note over client,tasks: Can raise exception for dependency, handled after response is sent
    Note over client,operation: Can raise HTTPException and can change the response
    client ->> dep: Start request
    Note over dep: Run code up to yield
    opt raise
        dep -->> handler: Raise HTTPException
        handler -->> client: HTTP error response
        dep -->> dep: Raise other exception
    end

    except Exception as e:
        errors: List[Exception] = []
        errors.append(e)
        try:
            data = vars(obj)
        except Exception as e:
            errors.append(e)
            raise ValueError(errors) from e
    return jsonable_encoder(
        data,
        include=include,
        exclude=exclude,
        by_alias=by_alias,
        exclude_unset=exclude_unset,

## Detalles Técnicos

Las versiones modernas de Python tienen soporte para **"código asíncrono"** usando algo llamado **"coroutines"**, usando la sintaxis **`async` y `await`**.

Veamos esa frase por partes en las secciones siguientes:

* **Código Asíncrono**
* **`async` y `await`**
* **Coroutines**

## Código Asíncrono

##### Новый язык не поддерживается

Если при запуске скрипта `./scripts/docs.py live` Вы получаете сообщение об ошибке, что язык не поддерживается, что-то вроде:

```
 raise TemplateNotFound(template)
jinja2.exceptions.TemplateNotFound: partials/language/xx.html
```

Сие означает, что тема не поддерживает этот язык (в данном случае с поддельным 2-буквенным кодом `xx`).

Aber dann, auch wenn Sie Ihre Burger noch nicht haben, ist Ihre Interaktion mit dem Kassierer erst mal „auf Pause“ ⏸, weil Sie warten müssen 🕙, bis Ihre Burger fertig sind.

    Note over client,operation: Can raise exceptions, including HTTPException
    client ->> dep: Start request
    Note over dep: Run code up to yield
    opt raise Exception
        dep -->> handler: Raise Exception
        handler -->> client: HTTP error response
    end
    dep ->> operation: Run dependency, e.g. DB session
    opt raise
        operation -->> dep: Raise Exception (e.g. HTTPException)
        opt handle

    sponsors = mkdocs.utils.yaml_load(sponsors_data_path.read_text(encoding="utf-8"))
    if not (match_start and match_end):
        raise RuntimeError("Couldn't auto-generate sponsors section")
    if not match_pre:
        raise RuntimeError("Couldn't find pre section (<style>) in index.md")
    frontmatter_end = match_pre.end()
    pre_end = match_start.end()
    post_start = match_end.start()

            except ImportError:
                logger.error(multipart_incorrect_install_error)
                raise RuntimeError(multipart_incorrect_install_error) from None
        except ImportError:
            logger.error(multipart_not_installed_error)
            raise RuntimeError(multipart_not_installed_error) from None


def get_param_sub_dependant(
    *,
    param_name: str,