Purpose
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As the 'function' tag is re-evaluated on the module update (even when noupdate="1"), the ir.model.data will be created a second time with the function 'create'.
This leads to the record deletion after the update when calling '_process_end'.
Specification
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Use '_update' instead of 'create' and '_update_dummy'.
- _update won't create another ir.model.data if it already exists.
- _update already calls _update_dummy to avoid the record deletion.