Question: who were the founding members of pink floyd
[{'answer': 'Nick Mason on drums', 'provenance': [{'wikipedia_id': '5079506', 'title': 'Pink Floyd', 'start_paragraph_id': 2, 'start_character': 75, 'end_paragraph_id': 2, 'end_character': 94, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Richard Wright on keyboards and vocals'}, {'answer': 'Syd Barrett on guitar and lead vocals'}, {'answer': 'Roger Waters on bass and vocals'}, {'provenance': [{'wikipedia_id': '5079506', 'title': 'Pink Floyd', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 844, 'bleu_score': 0.9613050207098811, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12278746499024996477}, 'section': 'Section::::Abstract.'}]}]