Question: who wrote river by eminem and ed sheeran
[{'answer': 'Marshall Mathers'}, {'answer': 'Ed Sheeran', 'provenance': [{'wikipedia_id': '55977910', 'title': 'River (Eminem song)', 'start_paragraph_id': 1, 'start_character': 96, 'end_paragraph_id': 1, 'end_character': 106, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Emile Haynie', 'provenance': [{'wikipedia_id': '55977910', 'title': 'River (Eminem song)', 'start_paragraph_id': 1, 'start_character': 226, 'end_paragraph_id': 1, 'end_character': 238, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]