Question: who played captain square in dad's army
[{'answer': 'Geoffrey Lumsden', 'provenance': [{'wikipedia_id': '5939267', 'title': "List of Dad's Army characters", 'start_paragraph_id': 88, 'start_character': 28, 'end_paragraph_id': 88, 'end_character': 44, 'bleu_score': 1.0, 'section': 'Section::::Other recurring characters.\n'}]}]