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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 get_certificate_expiration(self):
 """ Gets the certificate expiration from the certificate Gets the certificate expiration from the certificate file. Note that this value is stored into ``certificate_expiration`` when an instance is saved, so you should generally prefer that method (since this one requires reading and parsing the entire certificate). """

        datestring = self.certificate_object.get_notAfter().decode()
        dt = datetime.strptime(datestring, '%Y%m%d%H%M%SZ')
        return dt.replace(tzinfo=timezone.utc)