[Zope] Abstract ZClasses and containing classes

[Brian and JoAnn Burton]

Scenario: here is a hierarchy of ZClasses.


AbsDogPoundOrganization - abstract class
    ForProfitOrganization - subclass of AbsDogPoundOrganization
    NonProfitOrganization - subclass of AbsDogPoundOrganization


    Now I want AbsDogPoundOrganization to contain the class of Location (not
an abstract class).  First, what is the correct way to define an abstract
ZClass.  Do you make one that has no constructors?  The problem I see is
that then the subclasses of AbsDogPoundOrganization don't allow me to create
instances of Location within them.