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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_revocation_reason(self):
 """Get the revocation reason of this certificate."""

        if self.revoked is False:
            return

        if self.revoked_reason == '' or self.revoked_reason is None:
            return x509.ReasonFlags.unspecified
        else:
            return getattr(x509.ReasonFlags, self.revoked_reason)