One thing I've occasionally done to tame large functions is this: def frobWidget(widget): def frobCog(cog): ## stuff involving both cog and w

One thing I've occasionally done to tame large functions is this: def frobWidget(widget): def frobCog(cog): ## stuff involving both cog and widget ## stuff involving widget frobbedCogs = [frobCog(cog) for cog in widget] ## more stuff involving widget and frobbedCogs If frobCog were broken out into a separate function, then it would have to take widget as an argument, and if frobCog is never actually called from anywhere other than within frobWidget, then such separation makes the code harder to understand. Keeping the definition internal lets me take advantage of lexical scope; I can refer to widget within the definition of frobCog.