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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 subscribe(self, clock_name: str=None, clock_slots: Iterable[str]=None, subscriptions: Dict[str, Any]={}):
 		"""Subscribes this Area to the given Areas and optionally given Slots. Must be called before the Area is run. 		Args: 			clock_name: The name of the Area that is used as synchronizing Clock. 			clock_slots: The slots of the Clock relevant to this Area. 			subscriptions: A dictionary containing the relevant Areas names as keys and optionally the Slots as values. 		"""

		for area in subscriptions:  # type: str
			init_full(self, area, subscriptions[area])
			subscriptions[area] = {'slots': subscriptions[area]}

		if clock_name is not None:
			self.clock_name = clock_name
			self.clock_slots = clock_slots
			subscriptions[clock_name] = {'slots': clock_slots, 'buffer-length': 1}
		self.setup(puller=True, subscriptions=subscriptions)