Question: what is the first book of percy jackson
[{'answer': 'The Lightning Thief', 'provenance': [{'wikipedia_id': '6143564', 'title': 'Percy Jackson & the Olympians', 'start_paragraph_id': 4, 'start_character': 22, 'end_paragraph_id': 4, 'end_character': 41, 'bleu_score': 1.0, 'section': 'Section::::Origins.\n'}]}, {'provenance': [{'wikipedia_id': '6143564', 'title': 'Percy Jackson & the Olympians', 'start_paragraph_id': 8, 'start_character': 0, 'end_paragraph_id': 8, 'end_character': 86, 'bleu_score': 0.8852140475440831, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14394824283097876437}, 'section': 'Section::::Books.:"The Lightning Thief".\n'}]}, {'provenance': [{'wikipedia_id': '6143564', 'title': 'Percy Jackson & the Olympians', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 789, 'bleu_score': 0.9554313965184991, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14394824283097876437}, 'section': 'Section::::Origins.\n'}]}, {'provenance': [{'wikipedia_id': '21327279', 'title': 'Percy Jackson', 'section': 'Section::::Character.\n', 'start_paragraph_id': 7, 'end_paragraph_id': 7, 'meta': {'evidence_span': ['Percy\'s birthday is August 18. In the first novel of the series, "The Lightning Thief", he is twelve years old. His personality is described as "changeable like the sea" and hard to predict with the important exception that he is dangerously', 'In the first novel of the series, "The Lightning Thief', 'In the first novel of the series, "The Lightning Thief", he is twelve years old.']}}]}]