def test_loadNonExistentParent(self):
        """
        Loading a L{KnownHostsFile} from a path whose parent directory does not
        exist should result in an empty L{KnownHostsFile} that will save back
        to that path, creating its parent directory(ies) in the process.
        """
        thePath = FilePath(self.mktemp())
        knownHostsPath = thePath.child("foo").child(b"known_hosts")
        knownHostsFile = KnownHostsFile.fromPath(knownHostsPath)
        knownHostsFile.save()
        knownHostsPath.restat(False)
        self.assertTrue(knownHostsPath.exists())

        Loading a L{KnownHostsFile} from a path whose parent directory does not
        exist should result in an empty L{KnownHostsFile} that will save back
        to that path, creating its parent directory(ies) in the process.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_knownhosts.py