Better emulation of built-ins for testconf Bug fix: next is now in compat.__all__. Members of compat that do not correspond to built-ins or members of itertools are no longer added to built-ins while loading testconf. xrange is now added to built-ins only while loading testconf and only in legacy mode. testconf can now access the original built-ins through the CompatBuiltins context manager which is now exposed as config.builtins. Bug fix: the default string encoding is no longer relied upon.