You should to specify connection settings for MotorClient following these manuals:
MotorClient takes the same constructor arguments as MongoClient, as well as, http://emptysquare.net/motor/pymongo/api/motor/motor_client.html#motor.MotorClient,
http://emptysquare.net/motor/pymongo/api/pymongo/mongo_client.html#pymongo.mongo_client.MongoClient
"The host parameter can be a full mongodb URI, in addition to a simple
hostname. It can also be a list of hostnames or URIs. Any port
specified in the host string(s) will override the port parameter. If
multiple mongodb URIs containing database or auth information are
passed, the last database, username, and password present will be
used. For username and passwords reserved characters like ‘:’, ‘/’,
‘+’ and ‘@’ must be escaped following RFC 2396."
db = database = motor.MotorClient('mongodb://<dbuser>:<dbpassword>@ds047057.mongolab.com:47057/myDatabase
').open_sync().myDatabase