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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 """

        graph = self.call_map

        if graph is None:
            raise AngrGirlScoutError('Please generate the call graph first.')

        f = open(filepath, "wb")

        for src, dst in graph.edges():
            f.write("0x%x\tDirectEdge\t0x%x\n" % (src, dst))

        f.close()