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| product | mon | qty |
|---|---|---|
| A | 2018-01-01 | 5 |
| B | 2018-08-01 | 10 |
| D | 2018-10-01 | 12 |
| A | 2018-02-01 | 3 |
| A | 2018-03-01 | 0 |
| A | 2018-04-01 | 0 |
| A | 2018-05-01 | 5 |
| product | mon | qty |
|---|---|---|
| A | 2018-01-01 | 5 |
| B | 2018-08-01 | 10 |
| D | 2018-10-01 | 12 |
| A | 2018-02-01 | 3 |
| A | 2018-03-01 | 0 |
| A | 2018-04-01 | 0 |
| A | 2018-05-01 | 5 |