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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 diag_stressor(self, stressor, name=None):
 """ Diagonalize one row of the stressor matrix for a flow analysis. This method takes one row of the F matrix and diagonalize to the full region/sector format. Footprints calculation based on this matrix show the flow of embodied stressors from the source region/sector (row index) to the final consumer (column index). Note ---- Since the type of analysis based on the disaggregated matrix is based on flow, direct household emissions (FY) are not included. Parameters stressor : str or int - valid index for one row of the F matrix This must be a tuple for a multiindex, a string otherwise. The stressor to diagonalize. name : string (optional) The new name for the extension, if None (default):
 string based on the given stressor (row name) Returns ------- Extension """

        if type(stressor) is int:
            stressor = self.F.index[stressor]
        if len(stressor) == 1:
            stressor = stressor[0]
        if not name:
            if type(stressor) is str:
                name = stressor
            else:
                name = '_'.join(stressor) + '_diag'

        ext_diag = Extension(name)

        ext_diag.F = pd.DataFrame(
                index=self.F.columns,
                columns=self.F.columns,
                data=np.diag(self.F.loc[stressor, :])
                )
        try:
            ext_diag.unit = pd.DataFrame(
                    index=ext_diag.F.index,
                    columns=self.unit.columns,
                    data=self.unit.loc[stressor].unit)
        except AttributeError:
            # If no unit in stressor, self.unit.columns break
            ext_diag.unit = None

        return ext_diag