def _outputToTempFile(self, s):
        fname = self.mktemp()
        fObj = file(fname, 'w')
        fObj.write(s)
        fObj.close()
        return fname
Find the differences between the contents of this index and a tree.
dataset/ETHPy150Open twisted/nevow/nevow/test/test_athena.py/MemoizationTests._outputToTempFile--crossover with--dataset/ETHPy150Open natestedman/Observatory/observatory/lib/dulwich/index.py/Index.changes_from_tree