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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 playlist_song(self, playlist_song_id):
 		"""Get information about a playlist song. 		Note: 			This returns the playlist entry information only. 			For full song metadata, use :meth:`song` with 			the ``'trackId'`` field. 		Parameters: 			playlist_song_id (str):
 A playlist song ID. 		Returns: 			dict: Playlist song information. 		"""


		playlist_song_info = next(
			(
				playlist_song
				for playlist in self.playlists(include_songs=True)
				for playlist_song in playlist['tracks']
				if playlist_song['id'] == playlist_song_id
			),
			None
		)

		return playlist_song_info