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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _create_package_hierarchy(prefix=settings.TEMP_DIR, book_id=None):
 """ Create hierarchy of directories, at it is required in specification. `root_dir` is root of the package generated using :attr:`settings.TEMP_DIR` and :func:`_get_package_name`. `orig_dir` is path to the directory, where the data files are stored. `metadata_dir` is path to the directory with MODS metadata. Args: book_id (str, default None):
 UUID of the book. prefix (str, default settings.TEMP_DIR):
 Where the package will be stored. Default :attr:`settings.TEMP_DIR`. Warning: If the `root_dir` exists, it is REMOVED! Returns: list of str: root_dir, orig_dir, metadata_dir """

    root_dir = _get_package_name(book_id=book_id, prefix=prefix)

    if os.path.exists(root_dir):
        shutil.rmtree(root_dir)

    os.mkdir(root_dir)

    original_dir = os.path.join(root_dir, "original")
    metadata_dir = os.path.join(root_dir, "metadata")

    os.mkdir(original_dir)
    os.mkdir(metadata_dir)

    return root_dir, original_dir, metadata_dir