human
Complete this python program:
def default(task, app, consumer, info=logger.info, error=logger.error, task_reserved=task_reserved, to_system_tz=timezone.to_system, bytes=bytes, buffer_t=buffer_t, proto1_to_proto2=proto1_to_proto2):
assistant
#Here is the Python program you requested.

    """Default task execution strategy.
    Note:
    Strategies are here as an optimization, so sadly
    it\s not very easy to override.
    """
    hostname = consumer.hostname
    connection_errors = consumer.connection_errors
    _does_info = logger.isEnabledFor(logging.INFO)
    eventer = consumer.event_dispatcher
    events = (eventer and eventer.enabled)
    send_event = eventer.send
    task_sends_events = (events and task.send_events)
    call_at = consumer.timer.call_at
    apply_eta_task = consumer.apply_eta_task
    rate_limits_enabled = (not consumer.disable_rate_limits)
    get_bucket = consumer.task_buckets.__getitem__
    handle = consumer.on_task_request
    limit_task = consumer._limit_task
    body_can_be_buffer = consumer.pool.body_can_be_buffer
    Req = create_request_cls(Request, task, consumer.pool, hostname, eventer)
    revoked_tasks = consumer.controller.state.revoked
    def task_message_handler(message, body, ack, reject, callbacks, to_timestamp=to_timestamp):
        if (body is None):
            (body, headers, decoded, utc) = (message.body, message.headers, False, app.uses_utc_timezone())
            if (not body_can_be_buffer):
                body = (bytes(body) if isinstance(body, buffer_t) else body)
        else:
            (body, headers, decoded, utc) = proto1_to_proto2(message, body)
        req = Req(message, on_ack=ack, on_reject=reject, app=app, hostname=hostname, eventer=eventer, task=task, connection_errors=connection_errors, body=body, headers=headers, decoded=decoded, utc=utc)
        if _does_info:
            info(u'Received    task:    %s', req)
        if ((req.expires or (req.id in revoked_tasks)) and req.revoked()):
            return
        if task_sends_events:
            send_event(u'task-received', uuid=req.id, name=req.name, args=req.argsrepr, kwargs=req.kwargsrepr, root_id=req.root_id, parent_id=req.parent_id, retries=req.request_dict.get(u'retries', 0), eta=(req.eta and req.eta.isoformat()), expires=(req.expires and req.expires.isoformat()))
        if req.eta:
            try:
                if req.utc:
                    eta = to_timestamp(to_system_tz(req.eta))
                else:
 ...