Whatever happened to String Interpolation?

[Fernando Pérez]

I'm a big fan of Ka-Ping Yee's Itpl module (which allows strings of 
the form 'the value of x is $x', but I often find myself not using it 
so as not to add an extra dependency to a program I want to keep 
small.

There's PEP 215 (http://python.sourceforge.net/peps/pep-0215.html) 
where he proposed a simple and clean (IMHO) way to build this into 
the language.

I googled for a while and found very few things concerning it. Did 
this die? If so, why? It seems clean, unobtrusive and fantastically 
useful. Plus, I think it actually makes Python code much clearer in 
situations with complex string manipulations.

Does anyone know?

Cheers,

f.