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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def run(coro: 'Optional[Coroutine]' = None, *, loop: Optional[AbstractEventLoop] = None, shutdown_handler: Optional[Callable[[AbstractEventLoop], None]] = None, executor_workers: int = 10, executor: Optional[Executor] = None, use_uvloop: bool = False) -> None: """ Start up the event loop, and wait for a signal to shut down. :param coro: Optionally supply a coroutine. The loop will still run if missing. The loop will continue to run after the supplied coroutine finishes. The supplied coroutine is typically a "main" coroutine from which all other work is spawned. :param loop: Optionally supply your own loop. If missing, the default loop attached to the current thread context will be used, i.e., whatever ``asyncio.get_event_loop()`` returns. :param shutdown_handler: By default, SIGINT and SIGTERM will be handled and will stop the loop, thereby invoking the shutdown sequence. Alternatively you can supply your own shutdown handler function. It should conform to the type spec as shown in the function signature. :param executor_workers: The number of workers in the executor. (NOTE: ``run()`` creates a new executor instance internally, regardless of whether you supply your own loop.) :param executor: You can decide to use your own executor instance if you like. :param use_uvloop: The loop policy will be set to use uvloop. It is your responsibility to install uvloop. If missing, an ``ImportError`` will be raised. """

    logger.debug('Entering run()')

    assert not (loop and use_uvloop), (
        "'loop' and 'use_uvloop' parameters are mutually "
        "exclusive. (Just make your own uvloop and pass it in)."
    )
    if use_uvloop:
        import uvloop
        asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())

    loop_was_supplied = bool(loop)
    if not loop_was_supplied:
        loop = get_event_loop()

    if coro:
        async def new_coro():
            """During shutdown, run_until_complete() will exit
            if a CancelledError bubbles up from anything in the
            group. To counteract that, we'll try to handle
            any CancelledErrors that bubble up from the given
            coro. This isn't fool-proof: if the user doesn't
            provide a coro, and instead creates their own with
            loop.create_task, that task might bubble
            a CancelledError into the run_until_complete()."""
            try:
                await coro
            except asyncio.CancelledError:
                pass
        loop.create_task(new_coro())

    shutdown_handler = shutdown_handler or _shutdown_handler

    if WINDOWS:  # pragma: no cover
        # This is to allow CTRL-C to be detected in a timely fashion,
        # see: https://bugs.python.org/issue23057#msg246316
        loop.create_task(windows_support_wakeup())

        # This is to be able to handle SIGBREAK.
        def windows_handler(sig, frame):
            # Disable the handler so it won't be called again.
            signame = signal.Signals(sig).name
            logger.critical('Received signal: %s. Stopping the loop.', signame)
            shutdown_handler(loop)

        signal.signal(signal.SIGBREAK, windows_handler)
        signal.signal(signal.SIGINT, windows_handler)
    else:
        loop.add_signal_handler(SIGINT, shutdown_handler, loop)
        loop.add_signal_handler(SIGTERM, shutdown_handler, loop)

    # TODO: We probably don't want to create a different executor if the
    # TODO: loop was supplied. (User might have put stuff on that loop's
    # TODO: executor).
    if not executor:
        logger.debug('Creating default executor')
        executor = ThreadPoolExecutor(max_workers=executor_workers)
    loop.set_default_executor(executor)
    try:
        loop.run_forever()
    except KeyboardInterrupt:  # pragma: no cover
        logger.info('Got KeyboardInterrupt')
        if WINDOWS:
            # Windows doesn't do any POSIX signal handling, and no
            # abstraction layer for signals is currently implemented in
            # asyncio. So we fall back to KeyboardInterrupt (triggered
            # by the user/environment sending CTRL-C, or signal.CTRL_C_EVENT
            shutdown_handler()
    logger.info('Entering shutdown phase.')

    def sep():
        tasks = all_tasks(loop=loop)
        do_not_cancel = set()
        for t in tasks:
            # TODO: we don't need access to the coro. We could simply
            # TODO: store the task itself in the weakset.
            if t._coro in _DO_NOT_CANCEL_COROS:
                do_not_cancel.add(t)

        tasks -= do_not_cancel

        logger.info('Cancelling pending tasks.')
        for t in tasks:
            logger.debug('Cancelling task: %s', t)
            t.cancel()
        return tasks, do_not_cancel

    tasks, do_not_cancel = sep()
    # Here's a protip: if you group a bunch of tasks, and some of them
    # get cancelled, and they DON'T HANDLE THE CANCELLATION, then the
    # raised CancelledError will bubble up to, and stop the
    # loop.run_until_complete() line: meaning, not all the tasks in
    # the gathered group will actually be complete. You need to
    # enable this with the ``return_exceptions`` flag.
    group = gather(*tasks, *do_not_cancel, return_exceptions=True)
    logger.info('Running pending tasks till complete')
    # TODO: obtain all the results, and log any results that are exceptions
    # other than CancelledError. Will be useful for troubleshooting.
    loop.run_until_complete(group)

    logger.info('Waiting for executor shutdown.')
    executor.shutdown(wait=True)
    # If loop was supplied, it's up to the caller to close!
    if not loop_was_supplied:
        logger.info('Closing the loop.')
        loop.close()
    logger.critical('Leaving. Bye!')