def category_words():
		return ((cat, (word for i in instance_list for word in i)) for cat, instance_list in iteritems(train_instances))					

##################
## word scoring ##
##################
Query ActorStore for documentation
dataset/ETHPy150Open japerk/nltk-trainer/train_classifier.py/category_words--crossover with--dataset/ETHPy150Open EricssonResearch/calvin-base/calvin/runtime/north/calvincontrol.py/CalvinControl.handle_get_actor_doc