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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 download(self, song):
 		"""Download a song from a Google Music library. 		Parameters: 			song (dict):
 A song dict. 		Returns: 			tuple: Song content as bytestring, suggested filename. 		"""


		song_id = song['id']

		response = self._call(
			mm_calls.Export,
			self.uploader_id,
			song_id)
		audio = response.body
		suggested_filename = unquote(
			response.headers['Content-Disposition'].split("filename*=UTF-8''")[-1]
		)

		return (audio, suggested_filename)