Question: what is the significance of locks on bridges
[{'answer': 'to symbolize their love', 'provenance': [{'wikipedia_id': '6886172', 'title': 'Love lock', 'start_paragraph_id': 1, 'start_character': 126, 'end_paragraph_id': 1, 'end_character': 149, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '6886172', 'title': 'Love lock', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 275, 'bleu_score': 0.841020165317327, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9586680866939026051}, 'section': 'Section::::Abstract.'}]}]