Instead of exiting the interpreter, you can use reload() : see the section "Built-in functions" in the library reference
"reload( module) Reload a previously imported module. The argument must be a module object, so it must have been successfully imported before. This is useful if you have edited the module source file using an external editor and want to try out the new version without leaving the Python interpreter. The return value is the module object (the same as the module argument). " Pierre -- http://mail.python.org/mailman/listinfo/python-list
