Clear all object descriptors for stopped task. Task must be joined prior to calling this method.

		:return: None

def close_thread(self):
		""" Clear all object descriptors for stopped task. Task must be joined prior to calling this method.

		:return: None
		"""
		if self.__thread is not None and self.__thread.is_alive() is True:
			raise WThreadJoiningTimeoutError('Thread is still alive. Thread name: %s' % self.__thread.name)
		self.start_event().clear()
		self.__thread = None