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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 _cint(col, _map={base26(i):
 i - 1 for i in range(1, 257)}):
 """Return zero-based column index from bijective base26 string. 27 Traceback (most recent call last):
 ValueError: spam """

        try:
            return _map[col.upper()]
        except KeyError:
            raise ValueError(col)