'Return the values of default columns that were fetched using
the :meth:`.ValuesBase.return_defaults` feature.
The value is an instance of :class:`.RowProxy`, or ``None``
if :meth:`.ValuesBase.return_defaults` was not used or if the
backend does not support RETURNING.
.. versionadded:: 0.9.0
.. seealso::
:meth:`.ValuesBase.return_defaults`'

@property
def returned_defaults(self):

    return self.context.returned_defaults
