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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 create(self, identity, role_sid=values.unset, attributes=values.unset, friendly_name=values.unset):
 """ Create a new UserInstance :param unicode identity: The `identity` value that identifies the new resource's User :param unicode role_sid: The SID of the Role assigned to this user :param unicode attributes: A valid JSON string that contains application-specific data :param unicode friendly_name: A string to describe the new resource :returns: Newly created UserInstance :rtype: twilio.rest.chat.v2.service.user.UserInstance """

        data = values.of({
            'Identity': identity,
            'RoleSid': role_sid,
            'Attributes': attributes,
            'FriendlyName': friendly_name,
        })

        payload = self._version.create(
            'POST',
            self._uri,
            data=data,
        )

        return UserInstance(self._version, payload, service_sid=self._solution['service_sid'], )