OperationalError: (OperationalError) (2003, "Can't connect to MySQL server on '192.168.129.139' (111)") None None

I am trying to create a remote database using mysql on an Ubuntu machine running 12.04.

It has a root user with remote login enabled and no password.I have started the server.

output of

sudo netstat -tap | grep mysql

shows

tcp        0      0 localhost:mysql         *:*                     LISTEN      13246/mysqld

I have created a database called nwtopology using (as mentioned root doesn't have a password yet.)

 create database nwtopology
 grant all privileges on *.* to root@192.168.129.221
 FLUSH PRIVILEGES;

From the client machine that also runs Ubuntu 12.04 I use a python script to connect to the remote mysql database using sqlalchemy.

from pox.core import core
import pox.openflow.libopenflow_01 as of
import re
import datetime
import time
from sqlalchemy import create_engine, ForeignKey
from sqlalchemy import Column, Date, Integer, String
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship, backref
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from sqlalchemy.sql.expression import exists

log = core.getLogger()
engine = create_engine('mysql://root@192.168.129.139/nwtopology', echo=False)
Base = declarative_base()
Session = sessionmaker(bind=engine)
session = Session()

class SourcetoPort(Base):
    """"""
    __tablename__ = 'source_to_port'
    id = Column(Integer, primary_key=True)
    port_no        = Column(Integer)
    src_address    = Column(String,index=True)

    #-----------------------------------------
    def __init__(self, src_address,port_no):
        """"""
        self.src_address = src_address
        self.port_no     = port_no

The create_engine() call is failing with the following error.

POX 0.1.0 (betta) / Copyright 2011-2013 James McCauley, et al.
Traceback (most recent call last):
  File "/home/kart