As the northern hemisphere, that ambiguous spectral homeland we’re conscious of, starts to open up, it’s easy to be envious of the Australians who are plying their trade in the world of art and entertainment. Barrie Kosky, who’s finishing up as the head of Die Komische Oper in Berlin has just done a swag of operas – and will continue to do more even as he ceases to run the company – and of these nothing could be more thrilling and intimidating than to do Brecht /Weill’s The Threepenny Opera at the Berliner Ensemble.