code: def _lock(self, url: str, name: str, hash_: str):
          
          self._new_lock.append({
              'url': url,
              'name': name,
              'hash': hash_,
          })
          self._stale_files.pop(name, None)
docs: Add details of the files downloaded to _new_lock so they can be saved to the lock file.
          Also remove path from _stale_files, whatever remains at the end therefore is stale and can be deleted.