docs: def create_nv_link(self):
          """After a save(), write a link to the saved file using a non-versioned name"""
          from os.path import abspath, islink
          from os import unlink, symlink
  
          nv_name = self.doc.as_version(None)
  
          from_path =  abspath(self._last_write_path or self.package_path.path)
  
          to_path = join(dirname(from_path), nv_name + self.type_suffix)
  
          if islink(to_path):
              unlink(to_path)
  
          symlink(from_path, to_path)