This could be especially useful during testing, as it's very easy to override a dependency with your own custom settings.

### The config file { #the-config-file }

Coming from the previous example, your `config.py` file could look like:

{* ../../docs_src/settings/app02_an_py39/config.py hl[10] *}

Notice that now we don't create a default instance `settings = Settings()`.

### The main app file { #the-main-app-file }

The same example from above, returning an `HTMLResponse`, could look like:

{* ../../docs_src/custom_response/tutorial003_py39.py hl[2,7,19] *}

/// warning

The section:

```Python
from .routers import items, users
```

means:

* Starting in the same package that this module (the file `app/main.py`) lives in (the directory `app/`)...
* look for the subpackage `routers` (the directory at `app/routers/`)...
* and from it, import the submodule `items` (the file at `app/routers/items.py`) and `users` (the file at `app/routers/users.py`)...

	// already have the sizes from the central directory so we can
	// just ignore these.

	return nil
}

func readDirectoryEnd(r io.ReaderAt, size int64) (dir *directoryEnd, baseOffset int64, err error) {
	// look for directoryEndSignature in the last 1k, then in the last 65k
	var buf []byte
	var directoryEndOffset int64
	for i, bLen := range []int64{1024, 65 * 1024} {
		if bLen > size {
			bLen = size
		}

                  for (Integer node : graph.nodes()) {
                    Set<Integer> unused = graph.successors(node);
                  }
                  /*
                   * Also look up an earlier node so that, if the graph is using MapRetrievalCache,
                   * we read one of the fields declared in that class.
                   */
                  Set<Integer> unused = graph.successors(first);

# WARNING: THESE OPTIONS WONT WORK IF YOU DO NOT HAVE PROPER AUTHENTICATION AND PERMISSIONS

# Use --config=tf_public_cache to try and use the TensorFlow public build cache
# to build TensorFlow. Look at ci/official/envs to find which types of jobs
# push to the cache.  For macOS, use --config=tf_public_macos_cache

	}

	// Not necessarily needed but it ensures to the readers
	// eyes that we prefer a sorted setCount slice for the
	// subsequent function to figure out the right common
	// divisor, it avoids loops.
	slices.Sort(setCounts)

	return setCounts
}

// getSetIndexes returns list of indexes which provides the set size
// on each index, this function also determines the final set size

You would of course use the same ideas you read in [About FastAPI versions](versions.md){.internal-link target=_blank} to set the ranges of versions.

For example, your `requirements.txt` could look like:

```
fastapi[standard]>=0.113.0,<0.114.0
pydantic>=2.7.0,<3.0.0
```

And you would normally install those package dependencies with `pip`, for example:

<div class="termy">

```console

- Fixed a regression since 1.24 in the scheduling framework when overriding MultiPoint plugins (e.g. default plugins).

import org.codehaus.plexus.configuration.xml.XmlPlexusConfiguration;

/**
 * The bean containing the Mojo descriptor.<br>
 * For more information about the usage tag, have a look to:
 * <a href="https://maven.apache.org/developers/mojo-api-specification.html">
 * https://maven.apache.org/developers/mojo-api-specification.html</a>
 *
 * TODO is there a need for the delegation of MavenMojoDescriptor to this?