Definition: In this task, you are given a text which is the body of a document. Your job is to classify the topic of the document into these categories: 1)Company, 2)Educational Institution, 3)Artist, 4)Athlete, 5)Office Holder, 6)Mean of transportation, 7)Building, 8)Natural place, 9)Village, 10)Animal, 11)Plant, 12)Album, 13)Film, 14)Written work. Your output should be the category number. Don't generate anything apart from numbers 1-14.
Input: Text:  HMS Unity was a British U class submarine of the first group of that class built by Vickers Armstrong Barrow-in-Furness. She was laid down on 19 February 1937 and was commissioned on 5 October 1938.She served in home waters in the North Sea making a failed attack on the German submarine U-2.

6