Unpack a packed object, return an iterator
    Note: packed lists will be returned as tuples

def unpack(packed, object_hook=decode,
           list_hook=None, use_list=False, encoding='utf-8',
           unicode_errors='strict', object_pairs_hook=None,
           max_buffer_size=0, ext_hook=ExtType):
    """
    Unpack a packed object, return an iterator
    Note: packed lists will be returned as tuples
    """

    return Unpacker(packed, object_hook=object_hook,
                    list_hook=list_hook,
                    use_list=use_list, encoding=encoding,
                    unicode_errors=unicode_errors,
                    object_pairs_hook=object_pairs_hook,
                    max_buffer_size=max_buffer_size,
                    ext_hook=ext_hook)