Returns a dictionary with all song information.
        Use the :meth:`from_export` method to recreate the
        :class:`Song` object.

def export(self):
        """
        Returns a dictionary with all song information.
        Use the :meth:`from_export` method to recreate the
        :class:`Song` object.
        """
        return {'artists': self._artists,
                'radio': self._radio,
                'recent_artists': self._recent_artists,
                'songs_already_seen': self._songs_already_seen}