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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _toolkit_serialize_summary_struct(model, sections, section_titles):
 """ 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 """

    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