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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 _verify_student_input(self, student_input, locked):
 """If the student's answer is correct, returns the normalized answer. Otherwise, returns None. """

        guesses = [student_input]
        try:
            guesses.append(repr(ast.literal_eval(student_input)))
        except Exception:
            pass
        if student_input.title() in self.SPECIAL_INPUTS:
            guesses.append(student_input.title())
        for guess in guesses:
            if self._verify(guess, locked):
                return guess