<prompt> Translate the following text to EnglishCastro alifungwa katika gereza la kisiwa cha Pines sasa kinaitwa Isla de la Juventud hadi Mei 1955, wakati Batista alipotoa msamaha kwa wafungwa wa kisiasa.  <response>: Castro was incarcerated on the Isle of Pines now called the Isla de la Juventud until May 1955, when Batista granted an amnesty to political prisoners. 