'Update the RatePlanInstance
:param unicode unique_name: The unique_name
:param unicode friendly_name: The friendly_name
:returns: Updated RatePlanInstance
:rtype: twilio.rest.preview.wireless.rate_plan.RatePlanInstance'

def update(self, unique_name=values.unset, friendly_name=values.unset):

    data = values.of({'UniqueName': unique_name, 'FriendlyName': friendly_name})
    payload = self._version.update('POST', self._uri, data=data)
    return RatePlanInstance(self._version, payload, sid=self._solution['sid'])
