Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

Input: Consider Input: the family computer disk system was a disc add-on for the nintendo entertainment system that was only released in japan despite being announced in america.

Output: family computer disk system

Input: Consider Input: erzurum is a city in eastern anatolia (asian turkey).

Output: erzurum

Input: Consider Input: firooz bahram high school is one of tehran's oldest high schools.
Output: firooz bahram high school