Special case the "s#" PyArg_Parse() token for Unicode objects: "s#" will now return a pointer to the default encoded string data of the Unicode object instead of a pointer to the raw UTF-16 data. The latter is still available via PyObject_AsReadBuffer(). The patch also adds an optimization for string objects which is based on the fact that string objects return the raw character data for getreadbuffer access and are always single-segment.