How can I speed this function up?

[Łukasz Langa]

   Hi, Chris.
   I made a trivial testing framework for this cute problem and tried a 
couple of modifications. I also added the 10% of non-ELEMENT lines you 
mentioned. First thing, your updated algorithm didn't really get me much 
faster results than the original. I guess that my disk array sort of 
hides the multiple write penalty. But I experimented with various 
algorithms. Here's the code in its entirety: 
http://www.rafb.net/paste/results/ZuW4fK85.html My results (Python 2.4, 
32bit Fedora Core) were:

[ksh at lapoire tmp]# python test.py
Preparing data...
[write_data1] Preparing output file...
[write_data1] Writing...
[write_data1] Done in 10.73 seconds.
[write_data4] Preparing output file...
[write_data4] Writing...
[write_data4] Done in 10.46 seconds.
[write_data_flush] Preparing output file...
[write_data_flush] Writing...
[write_data_flush] Done in 9.09 seconds.
[write_data_per_line] Preparing output file...
[write_data_per_line] Writing...
[write_data_per_line] Done in 9.71 seconds.
[write_data_once] Preparing output file...
[write_data_once] Writing...
[write_data_once] Done in 7.82 seconds.

   I'm pretty sure that your measures will vary (observing your results 
you seem to have a faster CPU but slower disk(s)). But you can just take 
what works best for you. I'm also quite confident that you won't be able 
to catch up C since as you can see Python's data structures are far more 
flexible and thus require more processing overhead.

   Regards,
   Łukasz