Calling a matlab gui from python using pymatlab without allowing python to close it

[Ven]

Before proceeding further, my  system configuration is as follows:

Mac OS X 10.6.6
MATLAB 2010b
ActiveState Python 2.7

I have a gui built using matlab. I wrote the following python script
to open that matlab gui using pymatlab python module:

from pymatlab.matlab import MatlabSession

session = MatlabSession()
session.run('cd ~/ratter/ExperPort')
session.run('addpath(genpath(pwd))')
session.run('run Utility/WaterMeister/WaterMeister.m')

In the above python code, WaterMesiter.m is the matlab gui script. If
I run this in matlab shell, it opens the gui fine and I do whatever I
need to do with the gui and then close it. Now, instead, if I run the
above python script, everything goes fine but the GUI is closed
immediately as soon as it is opened, and the control is returned back
to python shell. I don't want this to happen. I want the GUI to stay
opened and I want the control to return back to python only when I
close the matlab GUI.

Any thoughts/suggestions will be greatly appreciated.