1972–73 Bulgarian Hockey League season
{'<entity_0>': '21st season of the Bulgarian Hockey League', '<entity_1>': '1972–73 Bulgarian Hockey League season', '<entity_2>': 'ice hockey', '<entity_3>': 'Bulgaria'}
[['1972–73 Bulgarian Hockey League season', 'sport', 'ice hockey'], ['1972–73 Bulgarian Hockey League season', 'country', 'Bulgaria'], ['1972–73 Bulgarian Hockey League season', 'description', '21st season of the Bulgarian Hockey League']]
The <entity_1> was the <entity_0>, the top level of <entity_2> in <entity_3>.
['sports season']