Question: when did trick or treating begin in america
[{'answer': '1920s', 'provenance': [{'wikipedia_id': '30861', 'title': 'Trick-or-treating', 'start_paragraph_id': 2, 'start_character': 679, 'end_paragraph_id': 2, 'end_character': 684, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '30861', 'title': 'Trick-or-treating', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 1247, 'bleu_score': 0.955797281362978, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15854937990493402703}, 'section': 'Section::::Abstract.'}]}]