code: func (mc MongoClient) EventById(id string) (contract.Event, error) {
  	s := mc.getSessionCopy()
  	defer s.Close()
  
  	query, err := idToBsonM(id)
  	if err != nil {
  		return contract.Event{}, err
  	}
  
  	var evt models.Event
  	if err := s.DB(mc.database.Name).C(db.EventsCollection).Find(query).One(&evt); err != nil {
  		return contract.Event{}, errorMap(err)
  	}
  	return evt.ToContract(mc)
  }
docs: // Get an event by id