[Zope] global variables in externa Methods

Hi, I want to set globale variables in external methods. With the following constuct I get errors if myFunctionA is set as function in the add external method form. Does anybody know how to set up global vars in external methods. -- many thanks for your replies, Elena #myExternalModul.py def myFunctionA(var1): global var1 myFunctionB() return def myFunctionB(): var2 = var1 return var2