code: def setSize(self, size, sizeIsEstimated):
          
          self._size = size
          self._sizeIsEstimated = sizeIsEstimated
  
          if self.fromVol is not None and size is not None and not sizeIsEstimated:
              Diff.theKnownSizes[self.toUUID][self.fromUUID] = size
docs: Update size.