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(define (note freq start len) (
	lambda (t) (
		if (or (< t start) (> t (+ start len)))
			0
			freq
	)
))

(define (music t) (
	(note 440 0 10) t
))

(define (play t) (
	if (< t 100)
		(cons (music t) (play (+ t 1)))
		(music t)
))

(display (play 0))