def METHOD_NAME(self):
    self.addCleanup(support.unlink, support.TESTFN)
    with open(support.TESTFN, "w") as fp:
        fp.write(SOURCE_3)
    lines = linecache.getlines(support.TESTFN)
    self.assertEqual(lines, ["\n", "def f():\n", "    return 3\n"])