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.
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Question: the vickers machine gun (also known as the vickers gun) was a machine gun that was used by the british army from 1912 to 1968.

Answer: vickers machine gun


Question: the flag of thailand has five stripes in the colours red, white, and blue.

Answer: flag of thailand


Question: joe the plumber, nickname of "samuel joseph "joe" wurzelbacher", (born december 3, 1973 in toledo, ohio) is an american commentator, motivational speaker and political activist.

Answer:
joe the plumber