code: def size(self):
          
          if 'length' in self.metainfo['info']:   # Singlefile
              return self.metainfo['info']['length']
          elif 'files' in self.metainfo['info']:  # Multifile torrent
              return sum(fileinfo['length']
                         for fileinfo in self.metainfo['info']['files'])
docs: Total size of content in bytes or ``None`` if :attr:`path` is ``None``