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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 list_tokens(self):
 """ ADMIN ONLY. Returns a dict containing tokens, endpoints, user info, and role metadata. """

        resp, resp_body = self.method_get("tokens/%s" % self.token, admin=True)
        if resp.status_code in (401, 403):
            raise exc.AuthorizationFailure("You must be an admin to make this "
                    "call.")
        return resp_body.get("access")