code: def _toolkit_serialize_summary_struct(model, sections, section_titles):
      
      output_dict = dict()
      output_dict['sections'] = [ [ ( field[0], __extract_model_summary_value(model, field[1]) ) \
                                                                              for field in section ]
                                                                              for section in sections ]
      output_dict['section_titles'] = section_titles
      return output_dict
docs: Serialize model summary into a dict with ordered lists of sections and section titles
  
      Parameters
      ----------
      model : Model object
      sections : Ordered list of lists (sections) of tuples (field,value)
        [
          [(field1, value1), (field2, value2)],
          [(field3, value3), (field4, value4)],
  
        ]
      section_titles : Ordered list of section titles
  
  
      Returns
      -------
      output_dict : A dict with two entries:
                      'sections' : ordered list with tuples of the form ('label',value)
                      'section_titles' : ordered list of section labels