How to retrieve object name by providing object id?

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Hi, I have run pr2_pick_and_place_demos and got object_id for a cup.

After retrieving the object id, I want to know the name of the detected object in data base, I found that there's a service handling this kind of request(which is stated here.)

But I cannot find this service with "rosservice list"(obviously it is not launched), I want to ask if anyone knows how to start this service so that I can request the name with this snippet of code.

Edit:

(The code below works if you create a package named getObjectName and depend this package on household_objects_database_msgs)

#!/usr/bin/env python
import roslib; 
roslib.load_manifest('getObjectName') #For loading srv in household_objects_database_msgs 

import rospy
from household_objects_database_msgs.srv import *

rospy.wait_for_service('/objects_database_node/get_model_description')
get_object_name=rospy.ServiceProxy('objects_database_node/get_model_description',GetModelDescription)
resp = get_object_name(18744) #Object id is 18744
print resp

Thanks in advance.