#2630: Implement PEP 3138.

The repr() of a string now contains printable Unicode characters unescaped.
The new ascii() builtin can be used to get a repr() with only ASCII characters in it.

PEP and patch were written by Atsuo Ishimoto.

Python/pythonrun.c

@@ -793,7 +793,7 @@ initstdio(void)
 	}
 	else {
 		if (!(std = PyFile_FromFd(fd, "<stderr>", "w", -1, encoding,
-					  errors, "\n", 0))) {
+					  "backslashreplace", "\n", 0))) {
 			goto error;
 		}
 	} /* if (fd < 0) */