Question: what was the russian policy enacted during the 1980s that meant for greater openness
[{'answer': 'Perestroika', 'provenance': [{'wikipedia_id': '24143', 'title': 'Perestroika', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 11, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '24143', 'title': 'Perestroika', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 376, 'bleu_score': 0.803251390331552, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2016720154030813497}, 'section': 'Section::::Abstract.'}]}]