[masklinn]

> However, in years of Python programming I can count the times I needed the ability on one hand. I haven't yet found a need for 'nonlocal'.

Might have to do with Python itself as well: because it's function-scoped and it tends to avoid higher-order function (in part due to the limitations of its anonymous functions), there are far less occasions write to lexical closures than in Scheme, Smalltalk or Ruby.