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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 append_row(self, index, value):
 """ Appends a row of value to the end of the data. Be very careful with this function as for sorted Series it will not enforce sort order. Use this only for speed when needed, be careful. :param index: index :param value: value :return: nothing """

        if index in self._index:
            raise IndexError('index already in Series')

        self._index.append(index)
        self._data.append(value)