Rocking Football..
..Enjoy..
import xmlrpclib
username = 'admin'
password = 'a'
database = 'test_60A'
sock_comm = xmlrpclib.ServerProxy('http://localhost:8069/xmlrpc/common')
uid = sock_comm.login(database,username,password)
sock = xmlrpclib.ServerProxy('http://localhost:8069/xmlrpc/object')
print "connection success full"
ids = sock.execute(database,uid, password,'res.company', 'search', [])
print "list of ids",ids
#ids will contain ids of company A and B
sock.execute(database,uid, password, 'res.company', 'write', ids, {'rml_header1': 'hop'})