Question: what is the function of the leaning tower of pisa
[{'answer': 'freestanding bell tower', 'provenance': [{'wikipedia_id': '46889', 'title': 'Leaning Tower of Pisa', 'start_paragraph_id': 1, 'start_character': 99, 'end_paragraph_id': 1, 'end_character': 122, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '46889', 'title': 'Leaning Tower of Pisa', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 434, 'bleu_score': 0.7866975083937081, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3027247747746153975}, 'section': 'Section::::Abstract.'}]}]