Print itself, only display attributes defined in
        :attr:`ExtendedBase._settings_major_attrs`

def glance(self):  # pragma: no cover
        """
        Print itself, only display attributes defined in
        :attr:`ExtendedBase._settings_major_attrs`
        """
        if self._settings_major_attrs is None:
            msg = ("Please specify attributes you want to include "
                   "in `class._settings_major_attrs`!")
            raise NotImplementedError(msg)

        kwargs = [
            (attr, getattr(self, attr))
            for attr in self._settings_major_attrs
        ]

        text = "{classname}({kwargs})".format(
            classname=self.__class__.__name__,
            kwargs=", ".join([
                "%s=%r" % (attr, value)
                for attr, value in kwargs
            ])
        )

        print(text)