code: def ensure_app_cache_dir(appname, *args):
      
      from ubelt import util_path
      dpath = get_app_cache_dir(appname, *args)
      util_path.ensuredir(dpath)
      return dpath
docs: Calls `get_app_cache_dir` but ensures the directory exists.
  
      Args:
          appname (str): the name of the application
          *args: any other subdirectories may be specified
  
      SeeAlso:
          get_app_cache_dir
  
      Example:
          >>> import ubelt as ub
          >>> dpath = ub.ensure_app_cache_dir('ubelt')
          >>> assert exists(dpath)