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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 unregisterThread(self, name):
 		""" 		Unregister the Thread registered under the given name. 		Make sure that the given Thread is properly stopped, or that a reference is 		kept in another place. Once unregistered, this class will not keep any 		other references to the Thread. 		Parameters 		name: string 			Name of the Thread to unregister 		"""

		if not name in self.thread_list:
			self.logger.error("Thread {0} is not registered!".format(name))
			raise Exception("Thread {0} is not registered!".format(name))

		del self.thread_list[name]
		self.logger.debug("Unregistered thread {0}".format(name))