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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 _check_tbit(self, **keys):
 """ Check if one of the columns is a TBIT column parameters colnums: integer array, optional """

        colnums = keys.get('colnums', None)

        if colnums is None:
            colnums = self._extract_colnums()

        has_tbit = False
        for i, colnum in enumerate(colnums):
            npy_type, isvar, istbit = self._get_tbl_numpy_dtype(colnum)
            if (istbit):
                has_tbit = True
                break

        return has_tbit