In PyFile_WriteString(), call PyUnicode_FromString() instead of
PyString_FromString().  This is arguably more correct, even if it
shouldn't matter much (all the input is likely to be ASCII).
diff --git a/Objects/fileobject.c b/Objects/fileobject.c
index 372cf43..34bca68 100644
--- a/Objects/fileobject.c
+++ b/Objects/fileobject.c
@@ -177,7 +177,7 @@
 		return -1;
 	}
 	else if (!PyErr_Occurred()) {
-		PyObject *v = PyString_FromString(s);
+		PyObject *v = PyUnicode_FromString(s);
 		int err;
 		if (v == NULL)
 			return -1;