Question: what commodity is much of venezuelas economy based
[{'answer': 'petroleum', 'provenance': [{'wikipedia_id': '32457', 'title': 'Economy of Venezuela', 'start_paragraph_id': 2, 'start_character': 44, 'end_paragraph_id': 2, 'end_character': 53, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '32457', 'title': 'Economy of Venezuela', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 943, 'bleu_score': 0.964580551124613, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15332671237028680600}, 'section': 'Section::::Abstract.'}]}]