Python GUI question

[sameer]

I am designing an application with wxPython which writes to a main
dictionary of objects which can be written out through pickling, or by
creating an object to sql wrapper, which writes to a database.  My
question is:

As I create new panels, is it better to 

a) keep creating methods in child panels that pass new data down to a
dictionary in the root panel ,

b) pass a reference in the constructor of each new panel to the
dictionary that contains all the data and implement some sort of lock
mechanism so only one panel can write to it, or

c) find a way to subclass each panel from the root panel so that the
main data dictionary can be implicitly accessed from anywhere?

I hope this is clear, and thanks for your help!