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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _format_local_file(self):
 """When args.local_file empty on Windows, tries to map args.entity to a unc path. Updates args.local_file in-place without returning anything. """


        if self.type != 'file':
            return

        if not self.entity:
            return

        if not is_win:
            return

        if self._file_exists():
            return

        self.args.local_file = self._to_unc_path(self.entity)