Question: when did they start building the african american museum
[{'answer': 'February 22 , 2012', 'provenance': [{'wikipedia_id': '3903010', 'title': 'National Museum of African American History and Culture', 'start_paragraph_id': 39, 'start_character': 51, 'end_paragraph_id': 39, 'end_character': 69, 'bleu_score': 1.0, 'section': 'Section::::Siting and design competition.:Construction of the museum building.\n'}]}, {'provenance': [{'wikipedia_id': '3903010', 'title': 'National Museum of African American History and Culture', 'start_paragraph_id': 39, 'start_character': 0, 'end_paragraph_id': 39, 'end_character': 343, 'bleu_score': 0.962600167205617, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8363906433866510446}, 'section': 'Section::::Siting and design competition.:Construction of the museum building.\n'}]}]