Assertion: codeine | /r/PartOf | two classes of drugs
Facets:
Source sentences:
text: Codeine belongs to two classes of drugs: the opioid and antitussives classes.
text: Codeine belongs to a class of medications called opiate (narcotic) analgesics and to a class of medications called antitussives.
text: Codeine belongs to the class of medications known as narcotic analgesics (pain relievers).