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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 _genenare_callmap_sif(self, filepath):
 """ Generate a sif file from the call map. :param filepath: Path of the sif file :return: None """

        with open(filepath, "wb") as f:
            for src, dst in self.callgraph.edges():
                f.write("%#x\tDirectEdge\t%#x\n" % (src, dst))