'Return the object as a ustar header block.'

def create_ustar_header(self, info):

    info['magic'] = POSIX_MAGIC
    if (len(info['linkname']) > LENGTH_LINK):
        raise ValueError('linkname    is    too    long')
    if (len(info['name']) > LENGTH_NAME):
        (info['prefix'], info['name']) = self._posix_split_name(info['name'])
    return self._create_header(info, USTAR_FORMAT)
