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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 _add_column(self, column):
 """ Add a new column to the DataFrame :param column: column name :return: nothing """

        self._columns.append(column)
        if self._blist:
            self._data.append(blist([None] * len(self._index)))
        else:
            self._data.append([None] * len(self._index))