listingsToLangMap :: M.Map String String
listingsToLangMap = M.fromList $ map switch langsList
  where switch (a,b) = (b,a)
listingsToLangMap :: M.Map String String
listingsToLangMap = M.fromList $ map switch langsList
  where switch (a,b) = (b,a)
listingsToLangMap = M.fromList $ map switch langsList
  where switch (a,b) = (b,a)