code: def add_archive_as_dir(self, zip_file_obj):
          
          BalancedDiscStorage._check_interface(zip_file_obj)
  
          file_hash = self._get_hash(zip_file_obj)
          dir_path = self._create_dir_path(file_hash)
          full_path = os.path.join(dir_path, file_hash)
  
          if os.path.exists(full_path):
              shutil.rmtree(full_path)
  
          os.mkdir(full_path)
  
          try:
              self._unpack_zip(zip_file_obj, full_path)
          except Exception:
              shutil.rmtree(full_path)
              raise
  
          return PathAndHash(path=full_path, hash=file_hash)
docs: Add archive to the storage and unpack it.
  
          Args:
              zip_file_obj (file): Opened file-like object.
  
          Returns:
              obj: Path where the `zip_file_obj` was unpacked wrapped in \
                   :class:`.PathAndHash` structure.
  
          Raises:
              ValueError: If there is too many files in .zip archive. \
                          See :attr:`._max_zipfiles` for details.
              AssertionError: If the `zip_file_obj` is not file-like object.