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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 compress(self, data_list):
 """Validates the captcha answer and returns the result If no data is provided, this method will simply return None. Otherwise, it will validate that the provided answer and timestamp hash to the supplied hash value, and that the timestamp is within the configured time that captchas are considered valid. """

        if data_list:
            # Calculate the hash of the supplied values
            hashed = self.widget.hash_answer(answer=data_list[0], timestamp=data_list[1])
            # Current time
            timestamp = time.time()

            if float(data_list[1]) < timestamp - DURATION:
                raise ValidationError("Captcha expired, please try again", code='invalid')
            elif hashed != data_list[2]:
                raise ValidationError("Incorrect answer", code='invalid')

            # Return the supplied answer
            return data_list[0]
        else:
            return None