code: async def refresh(self):
          
          cls = type(self)
          if hasattr(cls, 'read'):
              descriptors, alt_descriptors = get_pk_descriptors(cls)
              if len(descriptors) == 1:
                  try:
                      obj = await cls.read(getattr(self, descriptors[0][0]))
                  except AttributeError:
                      found = False
                      for alt_name, _ in alt_descriptors[0]:
                          if hasattr(self, alt_name):
                              obj = await cls.read(getattr(self, alt_name))
                              found = True
                              break
                      if not found:
                          raise
              elif len(descriptors) > 1:
                  args = []
                  for idx, (name, _) in enumerate(descriptors):
                      try:
                          args.append(getattr(self, name))
                      except AttributeError:
                          found = False
                          for alt_name, _ in alt_descriptors[idx]:
                              if hasattr(self, alt_name):
                                  args.append(getattr(self, alt_name))
                                  found = True
                                  break
                          if not found:
                              raise
                  obj = await cls.read(*args)
              else:
                  raise AttributeError(
                      "unable to perform 'refresh' no primary key "
                      "fields defined.")
              if type(obj) is cls:
                  self._data = obj._data
                  self._loaded = True
              else:
                  raise TypeError(
                      "result of '%s.read' must be '%s', not '%s'" % (
                          cls.__name__, cls.__name__, type(obj).__name__))
          else:
              raise AttributeError(
                  "'%s' object doesn't support refresh." % cls.__name__)
docs: Refresh the object from MAAS.