def instance_init(self, obj):
self.set_default_value(obj)<EOL>
This is called by :meth:`HasTraits.__new__` to finish init'ing.

        Some stages of initialization must be delayed until the parent
        :class:`HasTraits` instance has been created.  This method is
        called in :meth:`HasTraits.__new__` after the instance has been
        created.

        This method trigger the creation and validation of default values
        and also things like the resolution of str given class names in
        :class:`Type` and :class`Instance`.

        Parameters
        ----------
        obj : :class:`HasTraits` instance
            The parent :class:`HasTraits` instance that has just been
            created.