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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 _path_column(self):
 """Set ``include_path_column`` in csv_kwargs and returns path column name """

        path_column = self._csv_kwargs.get('include_path_column')

        if path_column is None:
            # if path column name is not set by user, set to a unique string to
            # avoid conflicts
            path_column = unique_string()
            self._csv_kwargs['include_path_column'] = path_column
        elif isinstance(path_column, bool):
            path_column = 'path'
            self._csv_kwargs['include_path_column'] = path_column
        return path_column