 Schemas
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   ┏━━━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━━━━┓
   ┃        In common        ┃       Right only        ┃
   ┃        3 columns        ┃        1 column         ┃
   ┡━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━┩
   │           ...           │ life_expectancy [Int64] │
   └─────────────────────────┴─────────────────────────┘
