def set_dotted(self, key, value):
        """
                qs.set_dotted('foo.bar', 'baz')

            is equivelent to:

                qs.foo.bar = baz
        """
        parts = key.split('.')
        cobj = self
        if len(parts) > 1:
            key = parts.pop()
            for name in parts:
                cobj = getattr(cobj, name)
        setattr(cobj, key, value)