Question: when do the monarch butterflies return to mexico
[{'answer': 'November', 'provenance': [{'wikipedia_id': '43794119', 'title': 'Monarch butterfly migration', 'start_paragraph_id': 2, 'start_character': 246, 'end_paragraph_id': 2, 'end_character': 254, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '43794119', 'title': 'Monarch butterfly migration', 'start_paragraph_id': 2, 'start_character': 57, 'end_paragraph_id': 2, 'end_character': 550, 'bleu_score': 0.5008955177529201, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9435211572049009484}, 'section': 'Section::::Abstract.'}]}]