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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 token(self) -> str: """ Return token identifying role to indy-sdk. :return: token: 'STEWARD', 'TRUSTEE', 'TRUST_ANCHOR', or None (for USER) """


        return self.value[0] if self in (Role.USER, Role.ROLE_REMOVE) else self.name