Question: when was anorexia classified as a mental illness
[{'answer': '1873', 'provenance': [{'wikipedia_id': '26534334', 'title': 'Anorexia nervosa', 'start_paragraph_id': 4, 'start_character': 944, 'end_paragraph_id': 4, 'end_character': 948, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '26534334', 'title': 'Anorexia nervosa', 'start_paragraph_id': 142, 'start_character': 0, 'end_paragraph_id': 142, 'end_character': 477, 'bleu_score': 0.9731482306711111, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17377431869002099944}, 'section': 'Section::::History.\n'}]}]