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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 column_type(self, column_name):
 """ Report column type as one of 'local', 'series', or 'function'. Parameters column_name : str Returns ------- col_type : {'local', 'series', 'function'} 'local' means that the column is part of the registered table, 'series' means the column is a registered Pandas Series, and 'function' means the column is a registered function providing a Pandas Series. """

        extra_cols = list_columns_for_table(self.name)

        if column_name in extra_cols:
            col = _COLUMNS[(self.name, column_name)]

            if isinstance(col, _SeriesWrapper):
                return 'series'
            elif isinstance(col, _ColumnFuncWrapper):
                return 'function'

        elif column_name in self.local_columns:
            return 'local'

        raise KeyError('column {!r} not found'.format(column_name))