return the directory name two directories up from the __file__ path, join it with 'conf' and 'locale' into valid path, separated by '/', basedirs is a list containing 2 elements: previous result and string 'locale'.
basedirs = [ os . path . join ( os . path . dirname ( os . path . dirname ( __file__ ) ) , 'conf' , 'locale' ) , 'locale' ]