* return which would render the timeout effectively useless.
             */
            doConnect();
        } catch (final Exception ex) {
            ex0 = ex; // Defer to below where we're locked
            return;
        } finally {
            synchronized (run_thread) {
                if (run_thread != thread) {
                    /* Thread no longer the one setup for this transport --

  private static final class ComplementRanges<C extends Comparable>
      extends ImmutableList<Range<C>> {

    private final ImmutableList<Range<C>> ranges;

    // True if the "positive" range set is empty or bounded below.
    private final boolean positiveBoundedBelow;

    // True if the "positive" range set is empty or bounded above.
    private final boolean positiveBoundedAbove;

    private final int size;

```Python hl_lines="1  4"
{!> ../../docs_src/python_types/tutorial009b.py!}
```

////

#### Using `Union` or `Optional` { #using-union-or-optional }

If you are using a Python version below 3.10, here's a tip from my very **subjective** point of view:

* 🚨 Avoid using `Optional[SomeType]`
* Instead ✨ **use `Union[SomeType, None]`** ✨.

         *
         * - above, where we return (in which case we never get here)
         *
         * - in `run`, which can't run until this Runnable is submitted to an executor, which
         *   doesn't happen until below. (And this Executor -- yes, the object is both a Runnable
         *   and an Executor -- is used for only a single `execute` call.)
         */

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		return fmt.Errorf("Invalid according to Policy: Policy expired")
	}

	// mustFindInPolicy is a map to list all the keys that we must find in the policy as
	// we process it below. At the end of checkPostPolicy function, if any key is left in
	// this map, that's an error.
	mustFindInPolicy := make(map[string][]string, len(formValues))
	for key, values := range formValues {

      Object form, made available under the License, as indicated by a
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      "Derivative Works" shall mean any work, whether in Source or Object
      form, that is based on (or derived from) the Work and for which the
      editorial revisions, annotations, elaborations, or other modifications