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| tel | firstname | lastname | customer_id |
|---|---|---|---|
| 1234 | Manu | Johns | 456 |
| 1234 | Manu | Johns | C456 |
| 13554 | Mathieu | Wainers | 4683 |
| 21234 | Fernand | Wajk | C389 |
| tel | firstname | lastname | customer_id |
|---|---|---|---|
| 1234 | Manu | Johns | C456 |
| 13554 | Mathieu | Wainers | 4683 |
| 21234 | Fernand | Wajk | C389 |