In that case, **FastAPI** also provides you with the tools to build it.

///

When we create an instance of the `OAuth2PasswordBearer` class we pass in the `tokenUrl` parameter. This parameter contains the URL that the client (the frontend running in the user's browser) will use to send the `username` and `password` in order to get a token.

//// tab | Python 3.9+

            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
            proxy_set_header X-NginX-Proxy true;

            # This is necessary to pass the correct IP to be hashed
            real_ip_header X-Real-IP;

            proxy_connect_timeout 300;
            
            # To support websocket
            proxy_http_version 1.1;

        this(time, properties != null ? properties.get(BUILD_TIMESTAMP_FORMAT_PROPERTY) : null);
    }

    /**
     *
     * @deprecated Use {@link #MavenBuildTimestamp(Date, Map)} or extract the format and pass it
     *             to {@link #MavenBuildTimestamp(Date, String)} instead.
     */
    @Deprecated
    public MavenBuildTimestamp(Date time, Properties properties) {

//
// The intention here is to use 64-78 in a way that matches the attempt in
// sysexits to signify some error running istioctl, and use 79-125 as custom
// error codes for other info that we'd like to use to pass info on.
const (
	ExitUnknownError   = 1 // for compatibility with existing exit code
	ExitIncorrectUsage = 64
	ExitDataError      = 65 // some format error with input data

// limitations under the License.

package configdump

import (
	"cmp"
	"encoding/json"
	"fmt"
	"strings"

	"sigs.k8s.io/yaml"

	"istio.io/istio/pkg/slices"
)

// ServiceFilter is used to pass filter information into service based config writer print functions
type ServiceFilter struct {
	Namespace string
}

// Verify returns true if the passed workload matches the filter fields

  # java version (default: java from PATH, currently $(java -version 2>&1 | grep version))
  -java-home <path>  Alternate JAVA_HOME

  # jvm options and output control
  -Dkey=val          Pass -Dkey=val directly to the java runtime
  -J-X               Pass option -X directly to the java runtime
                     (-J is stripped)

  # environment variables (read from context)
  JAVA_OPTS          Environment variable, if unset uses ""

                Assume.assumeTrue(false);
            }
            throw e;
        }
    }


    protected void testCredentialUrl ( String url, String user, String pass, String dom ) throws SmbException, MalformedURLException {
        try ( SmbFile f = new SmbFile(url) ) {
            Credentials creds = f.getContext().getCredentials();

            assertFalse(creds.isAnonymous());

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`.

// limitations under the License.

package configdump

import (
	"cmp"
	"encoding/json"
	"fmt"
	"strings"

	"sigs.k8s.io/yaml"

	"istio.io/istio/pkg/slices"
)

// PolicyFilter is used to pass filter information into service based config writer print functions
type PolicyFilter struct {
	Namespace string
}

// Verify returns true if the passed workload matches the filter fields

## Return a `Response` directly

You can also add headers when you return a `Response` directly.

Create a response as described in [Return a Response Directly](response-directly.md){.internal-link target=_blank} and pass the headers as an additional parameter:

```Python hl_lines="10-12"
{!../../docs_src/response_headers/tutorial001.py!}
```

/// note | "Technical Details"