[Zope] PropertySheets in python products

[Richard Jennings]

Hi,

on the 18 Nov last naveen wrote:

 >>  I am using python classes to for my Zope product. How do i add one more 
 >> property sheet to my python class.
 >> 
 >> I add the first one using the following code:
 >> 
 >> _properties=({'id':'title', 'type': 'string', 'mode': 'w'},
 >>              {'id':'color', 'type': 'string', 'mode': 'w'},
 >>              )
 >> 
 >> Since i already have about 25 properties on this property. i want to add 
 >> another property sheet as we do in ZOPE ZClass.

Dieter replied:
>Look at "OFS.PropertySheets.PropertySheets".

>You will need some investigation to see how to plug this in your
>custom class.

I have exactly the same problem, and Naveen did not post a solution and, as a newbie,
 I have tried to follow Dieter's advice but I have not been able to see the solution.

Can someone give me some further clues? 

for instance (no pun intended):
   PropertySheets.manage_addPropertySheet('mySheet', ns)
might work if I knew what namespace to use.

TIA
Richard