Question: when did the battle of hamel start and end
[{'answer': '4 July 1918', 'provenance': [{'wikipedia_id': '617583', 'title': 'Battle of Hamel', 'start_paragraph_id': 1, 'start_character': 21, 'end_paragraph_id': 1, 'end_character': 32, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '617583', 'title': 'Battle of Hamel', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 363, 'bleu_score': 0.9669306597086381, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12080622586715368817}, 'section': 'Section::::Abstract.'}]}]