Classify the relation of question with context to one of these categories: 1) award received, 2) based on, collection, 3) conflict, 4) constellation, 5) convicted of, 6) date of death, 7) director, 8) drafted by, 9) educated at, 10) medical condition, 11) military branch, 12) narrative location, 13) occupation, 14) original network, 15) parent company, 16) point in time, 17) production company, 18) residence, 19) series, 20) service entry, 21) sex or gender, 22) spouse, 23) standards body question.

Q: Context : The latest version has GTK+ support and a native Carbon port for Mac OS X. XEmacs has always had a very open development-environment, including anonymous CVS, later Mercurial access and publicly accessible development mailing-lists. 
Question : The XEmacs is based upon what?

A: based on
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Q: Context : What later became known as the Whirlpool Galaxy was discovered on October 13, 1773 by Charles Messier while hunting for objects that could confuse comet hunters, and was designated in Messier's catalogue as M51. 
Question : The star Whirlpool Galaxy is part of the constellation known as what?

A: constellation
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Q: Context : Rocketship X-M (aka Expedition Moon and originally as Rocketship Expedition Moon) is a 1950 American black-and-white science fiction film from Lippert Pictures, the first outer space adventure of the post-World War II era. 
Question : Which place does Rocketship X-M exist in?

A:
narrative location
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