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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 sigres_path(self):
 """Absolute path of the SIGRES file. Empty string if file is not present."""

        # Lazy property to avoid multiple calls to has_abiext.
        try:
            return self._sigres_path
        except AttributeError:
            path = self.outdir.has_abiext("SIGRES")
            if path: self._sigres_path = path
            return path