Question: when did the san diego chargers move to los angeles
[{'answer': '2017', 'provenance': [{'wikipedia_id': '9984506', 'title': 'History of the San Diego Chargers', 'start_paragraph_id': 1, 'start_character': 160, 'end_paragraph_id': 1, 'end_character': 164, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]