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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 update(self, friendly_name=values.unset, status=values.unset):
 """ Update the AccountInstance :param unicode friendly_name: FriendlyName to update :param AccountInstance.Status status: Status to update the Account with :returns: Updated AccountInstance :rtype: twilio.rest.api.v2010.account.AccountInstance """

        return self._proxy.update(friendly_name=friendly_name, status=status, )