def _set_umask(self, val):
        if val is not None:
            try:
                os.umask
            except __HOLE__:
                self.bus.log("umask function not available; ignoring umask.",
                             level=30)
                val = None
        self._umask = val
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/cherrypy/cherrypy/process/plugins.py/DropPrivileges._set_umask