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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 active_serving_watcher(backend, kitchen, period):
 """ Watches all cooking Recipes in a Kitchen Provide the kitchen name as an argument or be in a Kitchen folder. """

    err_str, use_kitchen = Backend.get_kitchen_from_user(kitchen)
    if use_kitchen is None:
        raise click.ClickException(err_str)
    click.secho('%s - Watching Active OrderRun Changes in Kitchen %s' % (get_datetime(), use_kitchen), fg='green')
    DKCloudCommandRunner.watch_active_servings(backend.dki, use_kitchen, period)
    while True:
        try:
            DKCloudCommandRunner.join_active_serving_watcher_thread_join()
            if not DKCloudCommandRunner.watcher_running():
                break
        except KeyboardInterrupt:
            print 'KeyboardInterrupt'
            exit_gracefully(None, None)
    exit(0)