Question: Which early leader of the Haitian Revolution conducted a secret ceremony during which the first major slave insurrection was planned in 1791?
{'answer': 'Dutty Boukman', 'supporting_facts': [['Bois Caïman', 0], ['Bois Caïman', 1], ['Bois Caïman', 2], ['Dutty Boukman', 0], ['Dutty Boukman', 1]]}