Question: when did humans begin to live in san francisco
[{'answer': '3000 BC', 'provenance': [{'wikipedia_id': '3602421', 'title': 'History of San Francisco', 'start_paragraph_id': 3, 'start_character': 92, 'end_paragraph_id': 3, 'end_character': 99, 'bleu_score': 1.0, 'section': 'Section::::Early history.\n'}]}, {'provenance': [{'wikipedia_id': '3602421', 'title': 'History of San Francisco', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 485, 'bleu_score': 0.9757530668325981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6828447384406340196}, 'section': 'Section::::Early history.\n'}]}]