def allowInstancesOf(self, *classes):
        """
        SecurityOptions.allowInstances(klass, klass, ...): allow instances
        of the specified classes

        This will also allow the 'instance', 'class' (renamed 'classobj' in
        Python 2.3), and 'module' types, as well as basic types.
        """
        self.allowBasicTypes()
        self.allowTypes("instance", "class", "classobj", "module")
        for klass in classes:
            self.allowTypes(qual(klass))
            self.allowModules(klass.__module__)
            self.allowedClasses[klass] = 1

        SecurityOptions.allowInstances(klass, klass, ...): allow instances
        of the specified classes

        This will also allow the 'instance', 'class' (renamed 'classobj' in
        Python 2.3), and 'module' types, as well as basic types.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/spread/jelly.py