'Grade a string response'

def get_score(self, student_answers):

    if (self.answer_id not in student_answers):
        correct = False
    else:
        student_answer = student_answers[self.answer_id].strip()
        correct = self.check_string(self.correct_answer, student_answer)
    return CorrectMap(self.answer_id, ('correct' if correct else 'incorrect'))
