[Python-ideas] Add a cryptographic hash (e.g SHA1) of source toPython Compiled objects?

[rocky at gnu.org]

Terry Reedy writes:
 > rocky at gnu.org wrote:
 > 
 > > Without a doubt you all are much more familiar at this stuff that I
 > > am. (In fact I'm a rank novice.) So I'd be grateful if someone would
 > > post code for a function say:
 > > 
 > >   compare_src_obj(python_src, python_obj)
 > > 
 > > that takes two strings -- a Python source filename and a Python object
 > > -- does what's outlined above, and returns a status which indicates
 > > the same or if not and if not whether the difference is because of the
 > > wrong version of Python was used.
 > 
 > Interesting question.  For equaility, I would start with, just guessing 
 > a bit:
 > 
 > marshal(compile(open(file.py).read())) == open(file.pyc).read()
 > 
 > Specifically for version clash, I believe the first 4 bytes are a magic 
 > version number.  If that is not part of the marshal string, it would 
 > need to be skipped for the equality comparison.

There's also the mtime that needs to be ignored mentioned in prior
posts. And is there a table which converts a magic number version back
into a string with the Python version number? Thanks.