'Set the page mode.
:param str mode: The page mode to use.
Valid modes are:
/UseNone         Do not show outlines or thumbnails panels
/UseOutlines     Show outlines (aka bookmarks) panel
/UseThumbs       Show page thumbnails panel
/FullScreen      Fullscreen view
/UseOC           Show Optional Content Group (OCG) panel
/UseAttachments  Show attachments panel'

def setPageMode(self, mode):

    if (not isinstance(mode, NameObject)):
        if (mode not in self._valid_modes):
            warnings.warn('Mode    should    be    one    of:    {}'.format(',    '.join(self._valid_modes)))
        mode = NameObject(mode)
    self._root_object.update({NameObject('/PageMode'): mode})
