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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 podcasts(self, *, device_id=None):
 		"""Get a listing of subsribed podcast series. 		Paramaters: 			device_id (str, Optional):
 A mobile device ID. 				Default: Use ``device_id`` of the :class:`MobileClient` instance. 		Returns: 			list: Podcast series dict. 		"""


		if device_id is None:
			device_id = self.device_id

		podcast_list = []
		for chunk in self.podcasts_iter(device_id=device_id, page_size=49995):
			podcast_list.extend(chunk)

		return podcast_list