code: def clear(self):
          
          not_removed = []
          for fn in os.listdir(self.base):
              fn = os.path.join(self.base, fn)
              try:
                  if os.path.islink(fn) or os.path.isfile(fn):
                      os.remove(fn)
                  elif os.path.isdir(fn):
                      shutil.rmtree(fn)
              except Exception:
                  not_removed.append(fn)
          return not_removed
docs: Clear the cache.