code: def update_server(self, datacenter_id, server_id, **kwargs):
          
          data = {}
  
          for attr, value in kwargs.items():
              if attr == 'boot_volume':
                  boot_volume_properties = {
                      "id": value
                  }
                  boot_volume_entities = {
                      "bootVolume": boot_volume_properties
                  }
                  data.update(boot_volume_entities)
              else:
                  data[self._underscore_to_camelcase(attr)] = value
  
          response = self._perform_request(
              url='/datacenters/%s/servers/%s' % (
                  datacenter_id,
                  server_id),
              method='PATCH',
              data=json.dumps(data))
  
          return response
docs: Updates a server with the parameters provided.
  
          :param      datacenter_id: The unique ID of the data center.
          :type       datacenter_id: ``str``
  
          :param      server_id: The unique ID of the server.
          :type       server_id: ``str``