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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def CheckForUnknownFiles(self):
 		"""Show an "are you sure?" prompt if there are unknown files."""

		unknown_files = self.GetUnknownFiles()
		if unknown_files:
			print "The following files are not added to version control:"
			for line in unknown_files:
				print line
			prompt = "Are you sure to continue?(y/N) "
			answer = raw_input(prompt).strip()
			if answer != "y":
				ErrorExit("User aborted")