why can't % operator use a list?

[Peter Hansen]

Andrew Dalke wrote:
> 
> Peter Hansen:
> > Although it's probably known as a Python wart, in that a single
> > %s works nicely with whatever is on the right-hand side except
> > when it's a tuple, it cannot be changed now without breaking a
> > lot of code, I'm sure.
> 
> Personally, I nearly always use the () syntax.  

(So do I, generally, but that doesn't change the likelihood of the
grammar changing to allow a list in place of a tuple, for the reason
I gave.)