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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 _columns_for_table(table_name):
 """ Return all of the columns registered for a given table. Parameters table_name : str Returns ------- columns : dict of column wrappers Keys will be column names. """

    return {cname: col
            for (tname, cname), col in _COLUMNS.items()
            if tname == table_name}