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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 _post_run_hook(self, runtime):
 """ there is not inner interface to run """

        self._fixed_image = self.inputs.after
        self._moving_image = self.inputs.before
        self._contour = self.inputs.wm_seg if isdefined(self.inputs.wm_seg) else None
        NIWORKFLOWS_LOG.info(
            'Report - setting before (%s) and after (%s) images',
            self._fixed_image, self._moving_image)

        return super(SimpleBeforeAfterRPT, self)._post_run_hook(runtime)