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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 generate_captcha(self):
 """Generated a fresh captcha This method randomly generates a simple captcha question. It then generates a timestamp for the current time, and signs the answer cryptographically to protect against tampering and replay attacks. """

        # Generate a fresh question
        self._question, answer = self._generate_question()

        # Get the current time, then sign the answer cryptographically
        timestamp = time.time()
        hashed = self.hash_answer(answer, timestamp)

        # Now stash all our values
        self._values = ['', timestamp, hashed]