How to protect Python source from modification

[Bugs]

As a side question Frank, how was your experiences using wxPython for 
your GUI?
Any regrets choosing wxPyton over another toolkit?
Was it very buggy?
How was it to work with in general?
Any other real-world wxPython feedback you have is appreciated.

Frank Millman wrote:
> I am writing a multi-user accounting/business system. Data is stored in
> a database (PostgreSQL on Linux, SQL Server on Windows). I have written
> a Python program to run on the client, which uses wxPython as a gui,
> and connects to the database via TCP/IP.
> 
<snip>