Question: when did flagrant fouls start in the nba
[{'answer': 'the 1990 - 91 season'}, {'provenance': [{'wikipedia_id': '3567040', 'title': 'Flagrant foul', 'start_paragraph_id': 3, 'start_character': 72, 'end_paragraph_id': 3, 'end_character': 249, 'bleu_score': 0.6224470099047681, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13189378486782681740}, 'section': 'Section::::NBA.\n'}]}]