{!> ../../../docs_src/response_model/tutorial003_01.py!}
    ```

With this, we get tooling support, from editors and mypy as this code is correct in terms of types, but we also get the data filtering from FastAPI.

How does this work? Let's check that out. 🤓

### Type Annotations and Tooling

First let's see how editors, mypy and other tools would see this.

    end
    Client--Plain-->CZ
    CZ-."HBONE (target)".->Server
    CZ--"HBONE (actual)"-->SZ
    SZ--Plain-->Server
```

### Pooling

User connections can be multiplexed over shared HBONE connections.
This is done through standard HTTP/2 pooling.
The pooling is keyed off the `{source identity, destination identity, destination ip}`.

### Headers

Ztunnel uses the following well-known headers in HBONE:

platforms/core-configuration/kotlin-dsl-provider-plugins/   @gradle/bt-kotlin-dsl-maintainers
platforms/core-configuration/kotlin-dsl-tooling-builders/   @gradle/bt-kotlin-dsl-maintainers
platforms/core-configuration/kotlin-dsl-tooling-models/     @gradle/bt-kotlin-dsl-maintainers

# Core automation platform (Declarative DSL)
platforms/core-configuration/declarative-dsl-api/               @gradle/bt-declarative-dsl

[19499] [INFO] Listening at: http://0.0.0.0:80 (19499)
[19499] [INFO] Using worker: uvicorn.workers.UvicornWorker
[19511] [INFO] Booting worker with pid: 19511
[19513] [INFO] Booting worker with pid: 19513
[19514] [INFO] Booting worker with pid: 19514
[19515] [INFO] Booting worker with pid: 19515
[19511] [INFO] Started server process [19511]
[19511] [INFO] Waiting for application startup.

[19499] [INFO] Listening at: http://0.0.0.0:80 (19499)
[19499] [INFO] Using worker: uvicorn.workers.UvicornWorker
[19511] [INFO] Booting worker with pid: 19511
[19513] [INFO] Booting worker with pid: 19513
[19514] [INFO] Booting worker with pid: 19514
[19515] [INFO] Booting worker with pid: 19515
[19511] [INFO] Started server process [19511]
[19511] [INFO] Waiting for application startup.

 * b0
 * --
 *
 * The inclusive start of the range. We get the first 14 bits of this code point from the section
 * and the last 7 bits from this byte.
 *
 * The end of the range is not encoded, but can be inferred by looking at the start of the range
 * that follows.
 *
 * b1
 * --
 *
 * This is either a mapping decision or the length of the mapped output, according to this table:
 *
 * ```

  It was the White Rabbit, trotting slowly back again, and
looking anxiously about as it went, as if it had lost something;
and she heard it muttering to itself `The Duchess!  The Duchess!
Oh my dear paws!  Oh my fur and whiskers!  She'll get me
executed, as sure as ferrets are ferrets!  Where CAN I have
dropped them, I wonder?'  Alice guessed in a moment that it was
looking for the fan and the pair of white kid gloves, and she

        "org/gradle/plugin/management/*",
        "org/gradle/plugins/**",
        "org/gradle/process/**",
        "org/gradle/testfixtures/**",
        "org/gradle/testing/jacoco/**",
        "org/gradle/tooling/**",
        "org/gradle/swiftpm/**",
        "org/gradle/model/**",
        "org/gradle/testkit/**",
        "org/gradle/testing/**",
        "org/gradle/vcs/**",
        "org/gradle/work/**",

[19499] [INFO] Listening at: http://0.0.0.0:80 (19499)
[19499] [INFO] Using worker: uvicorn.workers.UvicornWorker
[19511] [INFO] Booting worker with pid: 19511
[19513] [INFO] Booting worker with pid: 19513
[19514] [INFO] Booting worker with pid: 19514
[19515] [INFO] Booting worker with pid: 19515
[19511] [INFO] Started server process [19511]
[19511] [INFO] Waiting for application startup.

[19499] [INFO] Listening at: http://0.0.0.0:80 (19499)
[19499] [INFO] Using worker: uvicorn.workers.UvicornWorker
[19511] [INFO] Booting worker with pid: 19511
[19513] [INFO] Booting worker with pid: 19513
[19514] [INFO] Booting worker with pid: 19514
[19515] [INFO] Booting worker with pid: 19515
[19511] [INFO] Started server process [19511]
[19511] [INFO] Waiting for application startup.