From SF patch #852334.

who writes:

Here is batch 2, as a big collection of CVS context diffs.
Along with moving comments into docstrings, i've added a
couple of missing docstrings and attempted to make sure more
module docstrings begin with a one-line summary.

I did not add docstrings to the methods in profile.py for
fear of upsetting any careful optimizations there, though
i did move class documentation into class docstrings.

The convention i'm using is to leave credits/version/copyright
type of stuff in # comments, and move the rest of the descriptive
stuff about module usage into module docstrings.  Hope this is
okay.

    1. Comments at the beginning of the module, before
       functions, and before classes have been turned
       into docstrings.

    2. Tabs are normalized to four spaces.

Also, removed the "remove" function from dircmp.py, which reimplements
list.remove() (it must have been very old).

exceptions.

When raising NotANumber, pass the string that failed as the exception
value.