Question: how many sweeps have there been in the world series
[{'answer': '19', 'provenance': [{'wikipedia_id': '23489161', 'title': 'World Series', 'start_paragraph_id': 1, 'start_character': 116, 'end_paragraph_id': 1, 'end_character': 118, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '23489161', 'title': 'World Series', 'start_paragraph_id': 117, 'start_character': 0, 'end_paragraph_id': 117, 'end_character': 1048, 'bleu_score': 0.802050935860612, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10048627897929842614}, 'section': 'Section::::Modern World Series appearances by franchise.:Team patterns in the World Series.:Game-by-game.\n'}]}]