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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 verify(self):
 """ Performs additional validation steps which were not performed when this token was decoded. This method is part of the "public" API to indicate the intention that it may be overridden in subclasses. """

        # According to RFC 7519, the "exp" claim is OPTIONAL
        # (https://tools.ietf.org/html/rfc7519#section-4.1.4).  As a more
        # correct behavior for authorization tokens, we require an "exp"
        # claim.  We don't want any zombie tokens walking around.
        self.check_exp()

        # Ensure token id is present
        if api_settings.JTI_CLAIM not in self.payload:
            raise TokenError(_('Token has no id'))

        self.verify_token_type()