code: def send(self, diff):
          
          if not self.dryrun:
              self._fileSystemSync()
  
          return self.butter.send(
              self.getSendPath(diff.toVol),
              self.getSendPath(diff.fromVol),
              diff,
              self.showProgress is True,
          )
docs: Write the diff (toVol from fromVol) to the stream context manager.