def __init__(self, quiz_header=None, quiz_data_builder=None, 
         score_filer=None):
     if quiz_header == None:
         Quiz_Header.__init__(self, 'no_file.drill')
     else:
         Quiz_Header.__init__(self, quiz_header.file_path, 
                 quiz_header.quiz_type, quiz_header.question_topic, 
                 quiz_header.data_name, quiz_header.all_subquizzes)
     if quiz_data_builder == None:
         Quiz_Data.__init__(self)
     else:
         Quiz_Data.__init__(self, quiz_data_builder)
     if score_filer == None:
         self.score_filer = Score_Filer(self.file_path)
     else:
         self.score_filer = score_filer
     self.quiz = Weighted_Quiz(self.quiz_list, 
             self.score_filer.question_score)
     self.quiz.next()