<prompt> Translate the following text to SwahiliIt is believed that Leonardo da Vinci, whom Francois brought to the Loire Valley in 1516, participated in the design, especially of the central four-towered donjon which makes a dream palace out of a classically feudal castle keep and the celebrated double-ramped spiral staircase in the donjons center, which enables people to go up and down without meeting.  <response>: Leonardo da Vinci, ambaye Francois alimleta katika bonde la Loire mwaka 1516, alishiriki katika kubuni, hasa ya katikati ya minara minne ya donjon, ambayo hufanya jumba la ndoto nje ya classicly feudal ngome kuweka, na maarufu mara mbili-ramped spiral ngazi katika katikati ya donjon, ambayo inawezesha watu kwenda juu na chini bila kukutana. 