Martin Panter added the comment: It seems to me that the simplest fix is to document: 1. Struct.format attribute is a byte string 2. The input format strings for struct.pack(), Struct class, etc, are also allowed to be byte strings, for consistency (Issue 16349) Here is a patch that does that, and adds some simple test cases. ---------- keywords: +patch Added file: http://bugs.python.org/file37474/format-bytes.patch _______________________________________ Python tracker http://bugs.python.org/issue21071 _______________________________________