def __get_client(self):
'''Login to Google and return a ContactsClient object.
'''
if not self.__client:
if not self.config.email or not self.password:
print >> sys.stderr, "ERROR: Missing email or password"
sys.exit(1)
client = ContactsClient()
client.ssl = True
client.ClientLogin(email=self.config.email,
password=self.password,
service='cp',
source='goobook')
self.__client = client
return self.__client
