}
        });
    }

    /**
     * Retrieves a parameter value from the data store parameters map.
     *
     * @param paramMap the parameter map to search
     * @param key the parameter key to look up
     * @param defaultValue the default value to return if key is not found
     * @return the parameter value as a string, or the default value if not found
     */

# Background Tasks - `BackgroundTasks`

You can declare a parameter in a *path operation function* or dependency function with the type `BackgroundTasks`, and then you can use it to schedule the execution of background tasks after the response is sent.

You can import it directly from `fastapi`:

```python
from fastapi import BackgroundTasks
```

        // The method should write parameter words
        assertTrue(result >= 0, "writeParameterWordsWireFormat should return non-negative value");
    }

    @Test
    void testReadParameterWordsWireFormat() {
        byte[] buffer = new byte[1024];
        int result = response.readParameterWordsWireFormat(buffer, 0);

        // The method should read parameter words

* `items_s` değişkeni bir `set`'tir ve her bir öğesi `bytes` tipindedir.

#### Dict { #dict }

Bir `dict` tanımlamak için, virgülle ayrılmış 2 type parameter verirsiniz.

İlk type parameter, `dict`'in key'leri içindir.

İkinci type parameter, `dict`'in value'ları içindir:

{* ../../docs_src/python_types/tutorial008_py310.py hl[1] *}

Bu şu anlama gelir:

* `prices` değişkeni bir `dict`'tir:

# `Response` class

You can declare a parameter in a *path operation function* or dependency to be of type `Response` and then you can set data for the response like headers or cookies.

You can also use it directly to create an instance of it and return it from your *path operations*.

Read more about it in the [FastAPI docs about returning a custom Response](https://fastapi.tiangolo.com/advanced/response-directly/#returning-a-custom-response)

## OpenAPI operationId { #openapi-operationid }

/// warning | Achtung

Wenn Sie kein „Experte“ für OpenAPI sind, brauchen Sie dies wahrscheinlich nicht.

///

Mit dem Parameter `operation_id` können Sie die OpenAPI `operationId` festlegen, die in Ihrer *Pfadoperation* verwendet werden soll.

Sie müssten sicherstellen, dass sie für jede Operation eindeutig ist.

}

// ServeHTTP - implements http.Handler interface.
//
// When the `list` query parameter is provided (its value is ignored), the
// server lists all metrics that could be returned for the requested path.
//
// The (repeatable) `buckets` query parameter is a list of bucket names (or it
// could be a comma separated value) to return metrics with a bucket label.

# Security Tools

When you need to declare dependencies with OAuth2 scopes you use `Security()`.

But you still need to define what is the dependable, the callable that you pass as a parameter to `Depends()` or `Security()`.

There are multiple tools that you can use to create those dependables, and they get integrated into OpenAPI so they are shown in the automatic docs UI, they can be used by automatically generated clients and SDKs, etc.

    }

    /**
     * Adds an initial facet parameter mapping.
     *
     * @param key the parameter key
     * @param value the parameter value
     */
    public void addInitFacetParam(final String key, final String value) {
        initFacetParamMap.put(value, key);
    }

    /**
     * Gets the initial facet parameter mappings.
     *
     * @return the facet parameter map

    //                                  --------------------
    /**
     * Set the value of hostname, used in parameter comment. <br>
     * Even if empty string, treated as empty plainly. So "IF pmb != null" is false if empty.
     * @param hostname The parameter value of hostname. (NotNull)
     */
    public void setHostname(String hostname) {
        registerVariable("hostname", hostname);
    }