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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 _insert_row(self, i, index):
 """ Insert a new row in the DataFrame. :param i: index location to insert :param index: index value to insert into the index list :return: nothing """

        if i == len(self._index):
            self._add_row(index)
        else:
            self._index.insert(i, index)
            for c in range(len(self._columns)):
                self._data[c].insert(i, None)