Couple of nits:

- You added a removal of hotshot from setup.py to the patch; but that's
been checked in in the mean time.

- Why add an 'errors' argument to the function when it's a fatal error
to use it?

- Using 0 to autodetect the length is scary.  Normally we have two APIs
for that, one ..._FromString and one ...FromStringAndSize.  If you
really don't want that, please use -1, which is at least an illegal value.

- Why is there code in codeobject.c::PyCode_New() that still accepts a
PyString for the filename?

- In that file (and possibly others, I didn't check) your code uses
spaces to indent while the surrounding code uses tabs.  Moreover, your
space indent seems to assume there are 4 spaces to a tab, but all our
code (Python and C) is formatted assuming tabs are 8 spaces.  (The
indent isn't always 8 spaces -- but ASCII TAB characters always are 8,
for us.)

- Why copy the default encoding before mangling it?  With a little extra
care you will only have to copy it once.  Also, consider not mangling at
all, but assuming the encoding comes in a canonical form -- several
other functions assume that, e.g. PyUnicode_Decode() and
PyUnicode_AsEncodedString().

- I haven't run the unit tests yet.  Will be doing that next...