code: def ip_access_control_lists(self):
          
          if self._ip_access_control_lists is None:
              self._ip_access_control_lists = IpAccessControlListList(
                  self._version,
                  account_sid=self._solution['account_sid'],
              )
          return self._ip_access_control_lists
docs: Access the ip_access_control_lists
  
          :returns: twilio.rest.api.v2010.account.sip.ip_access_control_list.IpAccessControlListList
          :rtype: twilio.rest.api.v2010.account.sip.ip_access_control_list.IpAccessControlListList