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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_blank_row(self, label):
 """ Add a blank row with only an index value to self.df. This is done inplace. """

        col_labels = self.df.columns
        blank_item = pd.Series({}, index=col_labels, name=label)
        # use .loc to add in place (append won't do that)
        self.df.loc[blank_item.name] = blank_item
        return self.df