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.

Ex Input:
filisur is a former municipality of the district albula in the canton of graubünden in switzerland.

Ex Output:
filisur


Ex Input:
mae west (august 17, 1893 – november 22, 1980) was an american actress and movie star.

Ex Output:
mae west


Ex Input:
the university of siena (, unisi) is in siena, italy.

Ex Output:

university of siena