The keys of the `dict` identify each example, and each value is another `dict`.

Each specific example `dict` in the `examples` can contain:

* `summary`: Short description for the example.
* `description`: A long description that can contain Markdown text.
* `value`: This is the actual example shown, e.g. a `dict`.

For example, with an ID of `42`, this would render:

```html
<a href="/items/42">
```

## Templates and static files { #templates-and-static-files }

You can also use `url_for()` inside of the template, and use it, for example, with the `StaticFiles` you mounted with the `name="static"`.

```jinja hl_lines="4"

### Create metadata for tags { #create-metadata-for-tags }

Let's try that in an example with tags for `users` and `items`.

Create metadata for your tags and pass it to the `openapi_tags` parameter:

{* ../../docs_src/metadata/tutorial004.py hl[3:16,18] *}

Notice that you can use Markdown inside of the descriptions, for example "login" will be shown in bold (**login**) and "fancy" will be shown in italics (_fancy_).

/// tip

/// tip

The "PATCH" is the last number, for example, in `0.2.3`, the PATCH version is `3`.

///

So, you should be able to pin to a version like:

```txt
fastapi>=0.45.0,<0.46.0
```

Breaking changes and new features are added in "MINOR" versions.

/// tip

The "MINOR" is the number in the middle, for example, in `0.2.3`, the MINOR version is `2`.

///

## Example { #example }

Here's an example *path operation* with parameters using some of the above types.

{* ../../docs_src/extra_data_types/tutorial001_an_py310.py hl[1,3,12:16] *}

Note that the parameters inside the function have their natural data type, and you can, for example, perform normal date manipulations, like:

### Example Tools to Run at Startup { #example-tools-to-run-at-startup }

Some examples of the tools that can do this job are:

* Docker
* Kubernetes
* Docker Compose
* Docker in Swarm Mode
* Systemd

If you need to enforce it, use `OAuth2PasswordRequestFormStrict` instead of `OAuth2PasswordRequestForm`.

///

* An optional `client_id` (we don't need it for our example).
* An optional `client_secret` (we don't need it for our example).

/// info

The `OAuth2PasswordRequestForm` is not a special class for **FastAPI** as is `OAuth2PasswordBearer`.

For example, if you need to store it in a database.

For that, **FastAPI** provides a `jsonable_encoder()` function.

## Using the `jsonable_encoder` { #using-the-jsonable-encoder }

Let's imagine that you have a database `fake_db` that only receives JSON compatible data.

For example, it doesn't receive `datetime` objects, as those are not compatible with JSON.

### Multiple Applications { #multiple-applications }

In the same server (or servers), there could be **multiple applications**, for example, other API programs or a database.

Only one process can be handling the specific IP and port (the TLS Termination Proxy in our example) but the other applications/processes can be running on the server(s) too, as long as they don't try to use the same **combination of public IP and port**.

Because we are using a relative URL, if your API was located at `https://example.com/`, then it would refer to `https://example.com/token`. But if your API was located at `https://example.com/api/v1/`, then it would refer to `https://example.com/api/v1/token`.