Question: who is al mahdi and what will he accomplish
[{'answer': 'the prophesied redeemer of Islam'}, {'answer': 'will rid the world of evil'}, {'provenance': [{'wikipedia_id': '8914433', 'title': 'Mahdi', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 327, 'bleu_score': 0.505806736942297, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8943933835912835549}, 'section': 'Section::::Abstract.'}]}]