OK, so for fun I did a ran this on my machine (MacBook Pro, 2.53GHz, 10.8.4, 8GB ram, Python 2.7.2 shipped by Apple). I had to emulate the old timing module using code from [1].

    Method 1: 0.115 seconds
    Method 2: I gave up after >120s
    Method 3: 0.265
    Method 4: 0.160
    Method 5: 0.220
    Method 6: 0.098

I ran each one a few times to make sure the times were roughly correct. Method 6 is still the fastest, but the naive method one is really close. it obviously got optimized. Actually, they're all pretty close with the obvious (and hideous) outlier of using MutableString.

EDIT:

I just remembered I have an old version of PyPy (1.8) on my Mac. Thought I'd give that a try.

    Method 1: I gave up after >120s
    Method 2: I gave up after >120s
    Method 3: 0.090 seconds
    Method 4: 0.102
    Method 5: 0.430
    Method 6: 0.102

Method one is a problem again, and method 5 (the pseudo file) is noticeably slower. Otherwise the results aren't too far off.

[1] http://effbot.org/librarybook/timing.htm