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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 mobileclient(username=None, device_id=None, *, token=None, locale='en_US'):
 	"""Create and authenticate a Google Music mobile client. 	Parameters: 		username (str, Optional):
 Your Google Music username. 			This is used to store OAuth credentials for different accounts separately. 		device_id (str, Optional):
 A mobile device ID. Default: MAC address is used. 		token (dict, Optional):
 An OAuth token compatible with ``requests-oauthlib``. 		locale (str, Optional):
 `ICU <http://www.localeplanet.com/icu/>`__ locale used to localize some 			responses. This must be a locale supported by Android. Default: `'en_US'``. 	Returns: 		MobileClient: An authenticated :class:`~google_music.MobileClient` instance. 	"""


	return MobileClient(
		username,
		device_id,
		token=token,
		locale=locale
	)