Britain’s three major political parties wooed weary voters on Tuesday, all promising an end to Brexit wrangling if they win next month’s national election — but offering starkly different visions of how to achieve that. Prime Minister Boris Johnson says if his Conservative Party wins the Dec. 12 poll, he will get Parliament to ratify his divorce deal with the European Union and Britain will leave the bloc by Jan. 31. The main opposition Labour Party says it will take a bit longer — six months — to end more than three years of uncertainty triggered by voters’ decision in 2016 to leave the 28-nation EU after more than four decades of membership.