Question: when did the spanish first come to mexico
[{'answer': '1517', 'provenance': [{'wikipedia_id': '5865939', 'title': 'Spanish conquest of the Aztec Empire', 'start_paragraph_id': 2, 'start_character': 70, 'end_paragraph_id': 2, 'end_character': 74, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '5865939', 'title': 'Spanish conquest of the Aztec Empire', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 670, 'bleu_score': 0.750499274405344, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12489487485305988649}, 'section': 'Section::::Abstract.'}]}]