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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 _create_secret(self, length=12):
 """ Use a cryptograhically-secure Pseudorandom number generator for picking a combination of letters, digits, and punctuation to be our secret. :param length: how long to make the secret (12 seems ok most of the time) """

        # Charset will have 64 +- characters
        charset = string.digits + string.ascii_letters + '+-'
        return "".join(random.SystemRandom().choice(charset) for _ in
                range(length))