Get the global broker instance.  If no global broker is set,
    this initializes a RabbitmqBroker and returns it.

    Returns:
      Broker: The default Broker.

def get_broker() -> "Broker":
    """Get the global broker instance.  If no global broker is set,
    this initializes a RabbitmqBroker and returns it.

    Returns:
      Broker: The default Broker.
    """
    global global_broker
    if global_broker is None:
        from .brokers.rabbitmq import RabbitmqBroker

        set_broker(RabbitmqBroker(
            host="127.0.0.1",
            port=5672,
            heartbeat=5,
            connection_attempts=5,
            blocked_connection_timeout=30,
        ))
    return global_broker