Question: who was the chicano leader who worked to unionize agricultural workers
[{'answer': 'César Chávez', 'provenance': [{'wikipedia_id': '294510', 'title': 'United Farm Workers', 'start_paragraph_id': 1, 'start_character': 349, 'end_paragraph_id': 1, 'end_character': 361, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Dolores Huerta', 'provenance': [{'wikipedia_id': '294510', 'title': 'United Farm Workers', 'start_paragraph_id': 1, 'start_character': 366, 'end_paragraph_id': 1, 'end_character': 380, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '294510', 'title': 'United Farm Workers', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 791, 'bleu_score': 0.8595232736867001, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6338062645017095796}, 'section': 'Section::::Abstract.'}]}]