Question: when did lebron james join the cleveland cavaliers
[{'answer': '2003', 'provenance': [{'wikipedia_id': '240940', 'title': 'LeBron James', 'start_paragraph_id': 2, 'start_character': 222, 'end_paragraph_id': 2, 'end_character': 226, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]