docs: def _extract_ips(self, data):
          '''
          Extract ip addressess from openstack structure
          {
            'pl-krk-2-int-301-c2-int-1': [
             {
               'OS-EXT-IPS-MAC:mac_addr': 'fa:16:3e:29:f1:bb',
               'version': 4,
               'addr': '10.185.138.36',
               'OS-EXT-IPS:type': 'fixed'
            }
           ]
         }
         :arg data: dict
         :returns list
         '''
          result = []
          for region in data.items():
              for interface in region[1]:
                  result.append(interface['addr'])
          return result