Question: who headlined the first ever glastonbury festival in 1970
[{'answer': 'T. Rex', 'provenance': [{'wikipedia_id': '79026', 'title': 'Glastonbury Festival', 'start_paragraph_id': 9, 'start_character': 327, 'end_paragraph_id': 9, 'end_character': 333, 'bleu_score': 1.0, 'section': 'Section::::History.:1970s.:Pilton Festival 1970.\n'}]}, {'provenance': [{'wikipedia_id': '79026', 'title': 'Glastonbury Festival', 'start_paragraph_id': 9, 'start_character': 0, 'end_paragraph_id': 9, 'end_character': 423, 'bleu_score': 0.9720210313175831, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12302235806193753573}, 'section': 'Section::::History.:1970s.:Pilton Festival 1970.\n'}]}]