# File karel/karel_window.rb, line 326
     def place_beeper(street,avenue, number)
       # puts 'placing ' + number.to_s + ' at ' + street.to_s + ' ' + avenue.to_s
       beeper = Beeper.new(street, avenue, number, self)
       beeper.place
       @@Beepers [[street, avenue]] = beeper
     end