Question: how much is a shot of espresso in ml
[{'answer': '30 ml', 'provenance': [{'wikipedia_id': '47660', 'title': 'Espresso', 'start_paragraph_id': 32, 'start_character': 715, 'end_paragraph_id': 32, 'end_character': 720, 'bleu_score': 1.0, 'section': 'Section::::Shot variables.:Length.\n'}]}, {'provenance': [{'wikipedia_id': '47660', 'title': 'Espresso', 'start_paragraph_id': 43, 'start_character': 0, 'end_paragraph_id': 43, 'end_character': 152, 'bleu_score': 0.7993658519955711, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12044051801465280992}, 'section': 'Section::::Espresso-based drinks.\n'}]}]