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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 subscriptions(self):
 """Generator for the active subscriptions."""

        if _debug: ChangeOfValueServices._debug("subscriptions")

        subscription_list = []

        # loop through the object and detection list
        for obj, cov_detection in self.cov_detections.items():
            for cov in cov_detection.cov_subscriptions:
                subscription_list.append(cov)

        return subscription_list