'Grade student responses.  Called by capa_module.submit_problem.
`answers` is a dict of all the entries from request.POST, but with the first part
of each key removed (the string before the first "_").
Thus, for example, input_ID123 -> ID123, and input_fromjs_ID123 -> fromjs_ID123
Calls the Response for each question in this problem, to do the actual grading.'

def grade_answers(self, answers):

    self.student_answers = convert_files_to_filenames(answers)
    new_cmap = self.get_grade_from_current_answers(answers)
    self.correct_map = new_cmap
    return self.correct_map
