Question: when did the first episode of heartland come out
[{'answer': 'October 14 , 2007', 'provenance': [{'wikipedia_id': '13815059', 'title': 'List of Heartland episodes', 'start_paragraph_id': 1, 'start_character': 81, 'end_paragraph_id': 1, 'end_character': 98, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '13815059', 'title': 'List of Heartland episodes', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 243, 'bleu_score': 0.950578622812921, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16750932231729352426}, 'section': 'Section::::Abstract.'}]}]