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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 _get_package_name(prefix=settings.TEMP_DIR, book_id=None):
 """ Return package path. Use uuid to generate package's directory name. 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`. Returns: str: Path to the root directory. """

    if book_id is None:
        book_id = str(uuid.uuid4())

    return os.path.join(prefix, book_id)