Quote:
Return the index where to insert item x in list a, assuming a is sorted.
    
The return value i is such that all e in a[:i] have e < x, and all e in a[i:] have e >= x.  So if x already appears in the list, i points just before the leftmost x already there.

The last sentence is incorrect, and it contradicts what comes earlier. Not knowing which is correct, I had to test it in the shell.

>>> from bisect import *
>>> l = [1,2,3,3,3,4,5]
>>> bisect_left(l,3)
2
>>> l[2:]
[3, 3, 3, 4, 5]

It should be changed to read "i points at the leftmost x already there"

-Dan