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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 update(self, **kwargs):
 """ Overrides Django's update method to emit a post_bulk_operation signal when it completes. """

        ret_val = super(ManagerUtilsQuerySet, self).update(**kwargs)
        post_bulk_operation.send(sender=self.model, model=self.model)
        return ret_val