Designing questions

[pserrand]

I'm writing  a application wich contains abouth 50 inputscreen linked to
db-tables.
Each inputscreen has 2 classes
- 1 GUI class wich  construct the screen.
- 1 db class wich  do the db acces.

All the gui-classes are done at the moment, so i have the prototype of
the application.
And here's my problem :
The source code becomes realy long, wich gives a long time to load it. I
was thinking of spliting it in modules (1 module for each screen wich
contains the gui-class and the db-class) and then importing it when i
needed it, this is when the user makes the choice in the main-menu.
The question i have is how to 'unload' a module when i don't need it
anymore ? If i don't unload a module i would  have as many modules in
memory as the user has made choises in the main menu.
I think this could become a memory problem especailly since i'm using
gadfly as db, wich allso holds the tables in memory.

I really would appreciate some hints and comments here from experienced
guys who allready wrote BIG real world applications in PYTHON.

Pierrette
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