```

/// tip

The second argument to <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is the default value to return.

If not provided, it's `None` by default, here we provide `"World"` as the default value to use.

///

Then you could call that Python program:

//// tab | Linux, macOS, Windows Bash

<div class="termy">

```console

import java.util.concurrent.RejectedExecutionException;
import java.util.logging.Level;
import javax.annotation.CheckForNull;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *

	errFunctionNotImplemented = errors.New("Function is not yet implemented")
	errUnexpectedInvalidNode  = errors.New("Unexpected node value")
	errInvalidKeypath         = errors.New("A provided keypath is invalid")
)

// qProp contains analysis info about an SQL term.
type qProp struct {
	isAggregation, isRowFunc bool

	err error
}

// `combine` combines a pair of `qProp`s, so that errors are

   functions.

  > Note: The service mesh is not an overlay network. It
  > simplifies and enhances how microservices in an application talk to each
  > other over the network provided by the underlying platform.

- **Istiod** - The Istio control plane. It provides service discovery, configuration and certificate management. It consists of the following sub-components:

			}

			for _, kv := range r.Flags.Filter.Tags {
				for t, v := range tagMap {
					if kv.Match(BatchJobKV{Key: t, Value: v}) {
						return true
					}
				}
			}

			// None of the provided tags filter match skip the object
			return false
		}

		if len(r.Flags.Filter.Metadata) > 0 {
			for _, kv := range r.Flags.Filter.Metadata {
				for k, v := range info.Metadata {

}

// get ObjectOptions for Copy calls with encryption headers provided on the target side and source side metadata
func copyDstOpts(ctx context.Context, r *http.Request, bucket, object string, metadata map[string]string) (opts ObjectOptions, err error) {
	return putOptsFromReq(ctx, r, bucket, object, metadata)
}

// get ObjectOptions for Copy calls with encryption headers provided on the source side

    implements SetMultimap<K, V> {
  /**
   * Returns a {@link Collector} that accumulates elements into an {@code ImmutableSetMultimap}
   * whose keys and values are the result of applying the provided mapping functions to the input
   * elements.
   *
   * <p>For streams with defined encounter order (as defined in the Ordering section of the {@link
   * java.util.stream} Javadoc), that order is preserved, but entries are <a

            ),
        ] = "3.1.0"
        self.openapi_schema: Optional[Dict[str, Any]] = None
        if self.openapi_url:
            assert self.title, "A title must be provided for OpenAPI, e.g.: 'My API'"
            assert self.version, "A version must be provided for OpenAPI, e.g.: '2.1.0'"
        # TODO: remove when discarding the openapi_prefix parameter
        if openapi_prefix:
            logger.warning(

 * behavior of {@link #addAll}, which can lead to unexpected behavior. In this case, you should
 * override {@code addAll} as well, either providing your own implementation, or delegating to the
 * provided {@code standardAddAll} method.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations

The `Union` in `Union[str, None]` will allow your editor to give you better support and detect errors.

///

## Additional validation

We are going to enforce that even though `q` is optional, whenever it is provided, **its length doesn't exceed 50 characters**.

### Import `Query` and `Annotated`

To achieve that, first import:

* `Query` from `fastapi`