John Conyers, who represented Michigan’s 13th congressional district for 53 years, unceremoniously ended his political career yesterday. Conyers, 88, had been battling a staffer’s sexual-harassment allegations against him and buckled under pressure from party leader Nancy Pelosi and others to quit (he had planned to run for reelection next year). Additionally, new sexual-harassment claims from another staffer surfaced on Monday. Conyers became …