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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 _GetAuthCookie(self, auth_token):
 		"""Fetches authentication cookies for an authentication token. 		Args: 			auth_token: The authentication token returned by ClientLogin. 		Raises: 			HTTPError: If there was an error fetching the authentication cookies. 		"""

		# This is a dummy value to allow us to identify when we're successful.
		continue_location = "http://localhost/"
		args = {"continue": continue_location, "auth": auth_token}
		req = self._CreateRequest("https://%s/_ah/login?%s" % (self.host, urllib.urlencode(args)))
		try:
			response = self.opener.open(req)
		except urllib2.HTTPError, e:
			response = e
		if (response.code != 302 or
				response.info()["location"] != continue_location):
			raise urllib2.HTTPError(req.get_full_url(), response.code, response.msg, response.headers, response.fp)
		self.authenticated = True