Creates a mapper object on witch add_mapping() and remove_mapping()
    can be called. It uses fire-and-forget notifications so it has a very
    low overhead and latency but a little less guarantees.

def new_mapper(agent):
    """Creates a mapper object on witch add_mapping() and remove_mapping()
    can be called. It uses fire-and-forget notifications so it has a very
    low overhead and latency but a little less guarantees."""
    recp = recipient.Broadcast(MappingUpdatesPoster.protocol_id, 'lobby')
    return agent.initiate_protocol(MappingUpdatesPoster, recp)