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Since each job type module is executed in exactly the same way by the Worker, there must be some way to communicate to the Worker how to execute the module in such a way that is specific to your needsit in the specific way you need. The package is how that is done. In general, the package is a generic data structure, included in the job object, that can be accessed by the Worker's backend job module and used by that module to set up the job.
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