docs: def GetValues(self, fd):
      """Return the values for this attribute as stored in an AFF4Object."""
      result = None
      for result in fd.new_attributes.get(self, []):
        # We need to interpolate sub fields in this rdfvalue.
        if self.field_names:
          for x in self.GetSubFields(result, self.field_names):
            yield x
  
        else:
          yield result
  
      for result in fd.synced_attributes.get(self, []):
        result = result.ToRDFValue()
  
        # We need to interpolate sub fields in this rdfvalue.
        if result is not None:
          if self.field_names:
            for x in self.GetSubFields(result, self.field_names):
              yield x
  
          else:
            yield result
  
      if result is None:
        default = self.GetDefault(fd)
        if default is not None:
          yield default