/// tip

Prefer to use the `Annotated` version if possible.

///

```Python hl_lines="17"
{!> ../../docs_src/dependencies/tutorial006.py!}
```

////

These dependencies will be executed/solved the same way as normal dependencies. But their value (if they return any) won't be passed to your *path operation function*.

/// tip

Some editors check for unused function parameters, and show them as errors.

    protected List<String> getJvmArguments(Path rootDirectory) {
        if (rootDirectory != null) {
            // TODO: do this
            return null;
        }
        return null;
    }

    // TODO: same is in DefaultMavenParser!!! (duplication)
    @Override
    protected MavenOptions parseArgs(String source, List<String> args) throws ParserException {
        try {

)

// DrainBody close non nil response with any response Body.
// convenient wrapper to drain any remaining data on response body.
//
// Subsequently this allows golang http RoundTripper
// to reuse the same connection for future requests.
func DrainBody(respBody io.ReadCloser) {
	// Callers should close resp.Body when done reading from it.
	// If resp.Body is not closed, the Client's underlying RoundTripper

    * So, by using FastAPI you are saving development time, bugs, lines of code, and you would probably get the same performance (or better) you would if you didn't use it (as you would have to implement it all in your code).

http://127.0.0.1:8000/items/
```

would be the same as going to:

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

But if you go to, for example:

```
http://127.0.0.1:8000/items/?skip=20
```

The parameter values in your function will be:

* `skip=20`: because you set it in the URL
* `limit=10`: because that was the default value

## Optional parameters

///

/// note | "Technical Details"

You could also use `from starlette.templating import Jinja2Templates`.

**FastAPI** provides the same `starlette.templating` as `fastapi.templating` just as a convenience for you, the developer. But most of the available responses come directly from Starlette. The same with `Request` and `StaticFiles`.

///

## Writing templates

Then you can write a template at `templates/item.html` with, for example:

## Conditional OpenAPI from settings and env vars

You can easily use the same Pydantic settings to configure your generated OpenAPI and the docs UIs.

For example:

{* ../../docs_src/conditional_openapi/tutorial001.py hl[6,11] *}

Here we declare the setting `openapi_url` with the same default of `"/openapi.json"`.

And then we use it when creating the `FastAPI` app.

/**
 * A bimap (or "bidirectional map") is a map that preserves the uniqueness of its values as well as
 * that of its keys. This constraint enables bimaps to support an "inverse view", which is another
 * bimap containing the same entries as this bimap but with reversed keys and values.
 *
 * <h3>Implementations</h3>
 *
 * <ul>
 *   <li>{@link ImmutableBiMap}
 *   <li>{@link HashBiMap}
 *   <li>{@link EnumBiMap}

///

/// note | "Technical Details"

You could also use `from starlette.responses import JSONResponse`.

**FastAPI** provides the same `starlette.responses` as `fastapi.responses` just as a convenience for you, the developer. But most of the available responses come directly from Starlette. The same with `status`.

///

## OpenAPI and API docs

object file can then be combined with other objects into a package archive.

# Command Line

Usage:

	go tool asm [flags] file

The specified file must be a Go assembly file.
The same assembler is used for all target operating systems and architectures.
The GOOS and GOARCH environment variables set the desired target.

Flags:

	-D name[=value]
		Predefine symbol name with an optional simple value.