Question: who did the artwork for pink floyd's wall
[{'answer': 'Gerald Anthony Scarfe', 'provenance': [{'wikipedia_id': '210404', 'title': 'Gerald Scarfe', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 21, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '210404', 'title': 'Gerald Scarfe', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 189, 'bleu_score': 0.9364250605898111, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7563661940429272436}, 'section': 'Section::::Abstract.'}]}]