Question: what did the barons do in the feudal system
[{'answer': 'tenants - in - chief', 'provenance': [{'wikipedia_id': '2531852', 'title': 'Feudal baron', 'start_paragraph_id': 5, 'start_character': 464, 'end_paragraph_id': 5, 'end_character': 483, 'bleu_score': 1.0, 'section': 'Section::::England.\n'}]}, {'provenance': [{'wikipedia_id': '2531852', 'title': 'Feudal baron', 'start_paragraph_id': 3, 'start_character': 18, 'end_paragraph_id': 3, 'end_character': 609, 'bleu_score': 0.95800005925922, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16820986635050606711}, 'section': 'Section::::England.\n'}]}]