Returns a structured description of the model, including (where
        relevant) the schema of the training data, description of the training
        data, training statistics, and model hyperparameters.

        Returns
        -------
        sections : list (of list of tuples)
            A list of summary sections.
              Each section is a list.
                Each item in a section list is a tuple of the form:
                  ('<label>','<field>')

        section_titles: list
            A list of section titles.
              The order matches that of the 'sections' object.

def _get_summary_struct(self):
        """
        Returns a structured description of the model, including (where
        relevant) the schema of the training data, description of the training
        data, training statistics, and model hyperparameters.

        Returns
        -------
        sections : list (of list of tuples)
            A list of summary sections.
              Each section is a list.
                Each item in a section list is a tuple of the form:
                  ('<label>','<field>')

        section_titles: list
            A list of section titles.
              The order matches that of the 'sections' object.
        """
        section = []
        section_titles = ['Attributes']
        for f in self._list_fields():
            section.append( ("%s" % f,"%s"% f) )

        return ([section], section_titles)