SSH tunnel to MongoDB in Python

from sshtunnel import SSHTunnelForwarder
import pymongo
import pprint
import json

MONGO_HOST = "x.x.x.x"
MONGO_DB = "ids"
SSH_USER = "dmitri.telinov"
SSH_KEY = "/Users/dtelinov/.ssh/id_rsa"
SSH_KEY_PW = ""
server = SSHTunnelForwarder(
    (MONGO_HOST, 999),
    ssh_username=SSH_USER,
    ssh_pkey=SSH_KEY,
    ssh_private_key_password=SSH_KEY_PW,
    remote_bind_address=('127.0.0.1', 27017)
)

server.start()

client = pymongo.MongoClient('127.0.0.1', server.local_bind_port) # server.local_bind_port is assigned local port
db = client[MONGO_DB]

# execute search
for post in db.users.find( {"type" : "system"}, {"username.encryptedData":1,"_id":0} ):
    data = json.dumps(post)
    o = json.loads(data)

    print o['username']['encryptedData']

server.stop()