def init(self):
self.credentials = self._get_credentials()<EOL>self.http = self.credentials.authorize(httplib2.Http())<EOL>self.service = discovery.build(<EOL>'<STR_LIT>',<EOL>'<STR_LIT>',<EOL>http=self.http,<EOL>discoveryServiceUrl=DISCOVERY_URL,<EOL>)<EOL>
Fetch the credentials (and cache them on disk).