Question: who won the 2002 us open men's tennis championship
[{'answer': 'Pete Sampras', 'provenance': [{'wikipedia_id': '82666', 'title': '2002 US Open (tennis)', 'start_paragraph_id': 2, 'start_character': 317, 'end_paragraph_id': 2, 'end_character': 329, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '82666', 'title': '2002 US Open (tennis)', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 472, 'bleu_score': 0.976327165973018, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2223365899086806827}, 'section': 'Section::::Abstract.'}]}]