[Zope] increment value of self

I'm having a lot of problems with this one . I have an object (A) that has a method called increment, and a variable in the Basic propertysheet called count. I'd like other objects to be able to call that method, so that the A object increments the value of count + 1 when requested. The problem I'm having is that any other variables present in REQUEST are then also assigned to A. Here's what I have so far: """ increment """ c = context.count + 1 context.REQUEST.set('count',c) context.propertysheets.Basic.manage_editProperties(context.REQUEST)