global variables

[M.N.A.Smadi]

hi;
i have a project with multiple files in it.  I need to have a  varaible 
that will contain a value that will be modified in one file, and when 
coming back to the same file it should retain the same value.  The way 
am doing it right now, python is complaining about the variable being 
non-global

any clue?

thanks
m.smadi