Adding the following line to ~/.inputrc for bash commandline usage will break the python interactive interpreter.  Specifically, you can no longer type "space" characters:

Space: magic-space

This is fairly serious for bash users, because once you've lived with magic-space you don't ever want to live without it.

This was tested under 2 different operating systems (Ubuntu 9.10, FreeBSD 6.0) and 3 different python versions, so the problem seems widespread.

I didn't know what "magic space" is. But a quick google search shows that it is specific to Bash.

in http://www.ukuug.org/events/linux2003/papers/bash_tips/#S16
"""
There are other readline-based programs without this feature, so make it only apply in Bash:

$if Bash
  Space: magic-space
$endif

For example the MySQL client and the Perl debugger can also use the readline library.
"""

Python also uses the readline library; you should add the "$if Bash".

Didn't know about the inputrc conditional; that works.  I verified that magic-space (without the conditional) also interferes with mysql, so this seems like less of an oversight on the side of python and more of a bash-user-beware situation.

Anyway, thanks for the workaround!