'Flips screenreader setting.'

def func(self):

    new_setting = (not self.session.protocol_flags.get('SCREENREADER', False))
    self.session.protocol_flags['SCREENREADER'] = new_setting
    string = ('Screenreader    mode    turned    |w%s|n.' % ('on' if new_setting else 'off'))
    self.caller.msg(string)
    self.session.sessionhandler.session_portal_sync(self.session)
