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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 get_raw_column(table_name, column_name):
 """ Get a wrapped, registered column. This function cannot return columns that are part of wrapped DataFrames, it's only for columns registered directly through Orca. Parameters table_name : str column_name : str Returns ------- wrapped : _SeriesWrapper or _ColumnFuncWrapper """

    try:
        return _COLUMNS[(table_name, column_name)]
    except KeyError:
        raise KeyError('column {!r} not found for table {!r}'.format(
            column_name, table_name))