How to use the huey.contrib.djhuey.HUEY.lock_task function in huey

@HUEY.lock_task('regulate')
def regulate():
    updates_scheduled = 0

    rightnow = datetime.utcnow().replace(tzinfo=pytz.utc)

    for d in Dataset.objects.all():
        if d.keep_up_to_date is True:
            if not d.cache_last_updated:
                # Hasn't been udpated - run the update!
                update_layers(d.pk)
                update_time_cache(d.pk)
                updates_scheduled += 1
            else:
                run_another_update_after = d.cache_last_updated + timedelta(seconds=d.update_every)
                if rightnow > run_another_update_after:
                    # It is time for an update - run it!

def update_time_cache(pkey):
    with HUEY.lock_task('time-cache-{}'.format(pkey)):
        try:
            d = Dataset.objects.get(pk=pkey)
            d.update_time_cache()
            # Save without callbacks
            Dataset.objects.filter(pk=pkey).update(cache_last_updated=datetime.utcnow().replace(tzinfo=pytz.utc))
            return 'Updated {} ({!s})'.format(d.name, d.pk)
        except Dataset.DoesNotExist:
            return 'Dataset did not exist, can not complete task'
        except AttributeError:
            return 'No update_time_cache method on this dataset'

def update_dataset(pkey):
    with HUEY.lock_task('updating-{}'.format(pkey)):
        try:
            Dataset.objects.filter(pk=pkey).update(update_task='UPDATING')
            update_layers(pkey)
            update_time_cache(pkey)
            update_grid_cache(pkey)
            return 'Done'
        finally:
            Dataset.objects.filter(pk=pkey).update(update_task='')

def add_unidentified_dataset(pkey):
    with HUEY.lock_task('unidentified-{}'.format(pkey)):
        try:
            ud = UnidentifiedDataset.objects.get(pk=pkey)
            klass = Dataset.identify(ud.uri)
            if klass is not None:
                try:
                    ud.delete()
                    ds = klass.objects.create(name=ud.name, uri=ud.uri)
                    return 'Added {}'.format(ds.name)
                except IntegrityError:
                    msg = 'Could not add dataset, name "{}" already exists'.format(ud.name)
                    ud.messages = msg
                    ud.save()
                    return msg
            else:
                msg = 'No dataset types found to process {}'.format(ud.uri)
                ud.messages = msg