Bill Clinton uncorked an extended attack on Senator Bernie Sanders on Sunday, harshly criticizing Mr. Sanders and his supporters for what he described as inaccurate and “sexist” attacks on Hillary Clinton.br br “When you’re making a revolution you can’t be too careful with the facts,” Mr. Clinton said, deriding Mr. Sanders’s oft-mentioned call for a political revolution.br br The former president, addressing a few hundred supporters at a junior high school here, portrayed his wife’s opponent for the Democratic nomination as hypocritical, “hermetically sealed” and dishonest.