`tutorial/chapters` := [`intro.txt`,
			`name.txt`,
			`express.txt`,
			`setlist.txt`,
			`quiz1.txt`,
			`commands.txt`,
			`assign.txt`,
			`quotes.txt`,
			`surgery.txt`,
			`quiz2.txt`,
			`calculus.txt`,
			`algebra.txt`,
			`stats.txt`,
			`plotting.txt`,
			`program.txt`];

