Question: how many seasons were there of when calls the heart
[{'answer': '5', 'provenance': [{'wikipedia_id': '41630866', 'title': 'When Calls the Heart', 'start_paragraph_id': 8, 'start_character': 97, 'end_paragraph_id': 8, 'end_character': 98, 'bleu_score': 1.0, 'section': 'Section::::Plot.\n'}]}]