How to use the py2exe.build_exe.py2exe.finalize_options function in py2exe

def finalize_options(self):
            py2exe.build_exe.py2exe.finalize_options(self)
            if self.makensis is None:
                try:
                    import win32api
                    self.makensis = win32api.FindExecutable('makensis')
                except:
                    # Default path for makensis.  This is where it gets
                    # installed by default.
                    self.makensis = os.path.join(os.environ['ProgramFiles'], 'NSIS\\makensis')