/// info

Keep in mind that dataclasses can't do everything Pydantic models can do.

So, you might still need to use Pydantic models.

But if you have a bunch of dataclasses laying around, this is a nice trick to use them to power a web API using FastAPI. 🤓

///

## Dataclasses in `response_model` { #dataclasses-in-response-model }

You can also use `dataclasses` in the `response_model` parameter:

# Response Cookies { #response-cookies }

## Use a `Response` parameter { #use-a-response-parameter }

You can declare a parameter of type `Response` in your *path operation function*.

And then you can set cookies in that *temporal* response object.

{* ../../docs_src/response_cookies/tutorial002_py310.py hl[1, 8:9] *}

And then you can return any object you need, as you normally would (a `dict`, a database model, etc).

You can return a `RedirectResponse` directly:

{* ../../docs_src/custom_response/tutorial006_py310.py hl[2,9] *}

---

Or you can use it in the `response_class` parameter:


{* ../../docs_src/custom_response/tutorial006b_py310.py hl[2,7,9] *}

If you do that, then you can return the URL directly from your *path operation* function.

          MINIO_KMS_SECRET_KEY: "my-minio-key:OSMM+vkKUTCvQs9YL/CVMIMt43HFhkUpqJxTmGl6rYw="
          MINIO_KMS_AUTO_ENCRYPTION: on
        run: |
          sudo sysctl net.ipv6.conf.all.disable_ipv6=0
          sudo sysctl net.ipv6.conf.default.disable_ipv6=0
          make verify

```python
from typing import Any


def some_function(data: Any):
    print(data)
```

### Generic types { #generic-types }

Some types can take "type parameters" in square brackets, to define their internal types, for example a "list of strings" would be declared `list[str]`.

It is very helpful if you can prepare a reproduction of the bug. In other words, provide a small test case which we can run to confirm your bug. It makes it easier to find the problem and to fix it. Test cases should be provided as `curl` commands which we can copy and paste into a terminal to run it locally, for example:

```sh
# delete the index

# If the first character of an item is a question mark, the load will silently fail if the file does not exist.
${includes} = ?"${maven.user.conf}/maven-user.properties", \

* Many PRs don't have tests, you can **remind** them to add tests, or you can even **suggest** some tests yourself. That's one of the things that consume most time and you can help a lot with that.

* Then also comment what you tried, that way I'll know that you checked it. 🤓

## Create a Pull Request { #create-a-pull-request }

fi

if [ -e /etc/sysctl.d/99-gce.conf ]; then
  # The GCE defaults disable IPv4 forwarding, which breaks the Docker
  # build. Workaround this by renaming the file so that it is executed
  # earlier than our own overrides.
  #
  # This ultimately needs to be fixed at the image level - see infra
  # issue 15654.
  sudo mv /etc/sysctl.d/99-gce.conf /etc/sysctl.d/98-gce.conf
fi

# Required by bats

You can use the same dependency *functions* you use normally.

### Dependency requirements { #dependency-requirements }

They can declare request requirements (like headers) or other sub-dependencies:

{* ../../docs_src/dependencies/tutorial006_an_py310.py hl[8,13] *}

### Raise exceptions { #raise-exceptions }

These dependencies can `raise` exceptions, the same as normal dependencies: