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| string | substring |
|---|---|
| FLAT 3, thanos house, nw1 6fs | 3 |
| FLAT 3B, thanos house, nw1 6fs | 3B |
| 324, thanos house, nw1 6fs | 324 |
| APARTMENT 324, thanos house, nw1 6fs | 324 |
SELECT 4