[Zope] ZClass question - array of arrays

[Dianne Van Dulken]

Hi, 

I'm having a little bit of a problem working out what ZClass property I
should be setting.  I want to record an array that can either contain
strings or more arrays.

eg:

It can be 

['a', 'b', 'c'] 

or 

['a', ['b', 'c'], 'd']

or 

[['a','b'], ['c','d'], ['e','f']]

The problem is that I can't work out what property type I should be setting
this to be.  I tried tokens, but tokens won't allow arrays to be saved, and
both lines and strings assume that there will be a string (obviously), which
means that I have to do a lot of splitting on [ and , before I can work with
the data.  The whole idea of the property is that if there is a scalar in
position X, it shows the scalar, otherwise with an array, it shows a random
value from that array.

Is there an obvious type that I am missing?

Thanks

Dianne