I am running mint 13 and have python 3.2 installed using the apt-get package management system. I also have python 2.7 installed along with 3.2 The pycompile seems to be the one that packages python 2.7 code and and throws exceptions for python 3.2 code.
I have looked around and tried to install a few packages, but have not been able to find pycompile for python 3.2. How do I get pycompile work for python 3.2?
py_compile is a stdlib module that can produce byte-code given Python source. It is rarely needed.
To compile Python 3 source code you must use py_compile version included with it and not the version from Python 2.7 if you use it from a command-line:
$ python3 -m py_compile your_script.py
To change the default location where pyc-files are stored you could use cfile parameter of the py_compile.compile() function.
Does the byte code make the script run any faster?
It might (by a minuscule amount). Python compiler doesn't do much so it is fast.
Here's an example how byte-code looks like in a human readable form:
>>> def f(o):
... with o:
... pass
...
>>> import dis
>>> dis.dis(f)
2 0 LOAD_FAST 0 (o)
3 SETUP_WITH 5 (to 11)
6 POP_TOP
3 7 POP_BLOCK
8 LOAD_CONST 0 (None)
>> 11 WITH_CLEANUP
12 END_FINALLY
13 LOAD_CONST 0 (None)
16 RETURN_VALUE
All heavy lifting is left for the python interpreter that interprets the byte-code at runtime.
Or is this only for distribution?
The docs provide a use-case: a shared directory with Python modules where only curtain users can write. You can disable caching byte-code to disk so it is possible to use py-files that stored in read-only locations without corresponding pyc-files.
Why is it rarely used?
Usually the pyc-files are created by building/installation process. If there is no pyc-files they can be created on-the-fly when you import a module:
$ python -c 'import some_module'