> a very, very old part of Python that predates the conventions now considered good style. Using space delimiters for lists of strings is a common idiom in Perl

> a very, very old part of Python that predates the conventions now considered good style. Using space delimiters for lists of strings is a common idiom in Perl scripting due to the `qw()` quote syntax. Note that the Smalltalk-80 class creation method also expects a space-separated string of instance variable names, and that's an environment considerably older than Perl.