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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def save(self):
 """ Persists the current job metadata to MongoDB. Will be called at each worker report. """


        if not self.saved and self.data and "progress" in self.data:
            # TODO should we save more fields?
            self.collection.update({"_id": self.id}, {"$set": {
                "progress": self.data["progress"]
            }})
            self.saved = True