True/False

[Skip Montanaro]

    Ian> True, False = 1==1, 0==1

Why not

    try:
        True
    except NameError:
        True, False = 1==1, 0==1

?  Should work anywhere without complaints.

    Ian> Is there any reason why reassigning True and False will be a
    Ian> problem in the future?

The builtins may get "tightened up" in the future.  This particular idiom
probably won't be affected, but you may not be able to (easily) shadow a
builtin in another module's global namespace, e.g.:

    import a
    a.True, a.False = 1==1, 0==1

might not be possible.  The idea here is to allow the byte compiler to know
all the possible builtin shadowing that goes on in a module by examining
just the module itself.  This, in turn, would allow access to builtins (and
globals to some extent I think) to be optimized.

    Ian> Should I tell people who are putting in version tests that it isn't
    Ian> necessary?

Testing against particular versions is generally not a good idea.  I'd test
against the presence of the object in question instead.

Skip