Question: who acquired the rights for the book 'shrek ' in 1991
[{'answer': 'Steven Spielberg', 'provenance': [{'wikipedia_id': '4324892', 'title': 'Shrek!', 'start_paragraph_id': 9, 'start_character': 0, 'end_paragraph_id': 9, 'end_character': 16, 'bleu_score': 1.0, 'section': 'Section::::Adaptations.\n'}]}, {'provenance': [{'wikipedia_id': '4324892', 'title': 'Shrek!', 'start_paragraph_id': 9, 'start_character': 0, 'end_paragraph_id': 9, 'end_character': 433, 'bleu_score': 0.9716239638199891, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12625756709359862461}, 'section': 'Section::::Adaptations.\n'}]}]