[Zope] getting base classes's (super class) _properties tuple

[Daniel Rusch]

Say I have a fully functional (and more importantly, working) Product
will call A.

I want to extend this Product's capabilities so I wish to derive another

class from it, call it B.

No problem,

class B(A):
    .........

now in class B I want to add a new property.

Is the a way of getting the base (super) class _properties tuple and
just adding the new one to it. Since a tuple is an immutable object I
can't do this:
_properties=A._properties.append({'id':'RenderStandardHeader',
'type':'int','mode':'w'})

Any thoughts ????

DR