def irc_WHO(self, prefix, params):
        """Who query

        Parameters: [ <mask> [ "o" ] ]
        """
        #<< who #python
        #>> :x.opn 352 glyph #python aquarius pc-62-31-193-114-du.blueyonder.co.uk y.opn Aquarius H :3 Aquarius
        # ...
        #>> :x.opn 352 glyph #python foobar europa.tranquility.net z.opn skreech H :0 skreech
        #>> :x.opn 315 glyph #python :End of /WHO list.
        ### also
        #<< who glyph
        #>> :x.opn 352 glyph #python glyph adsl-64-123-27-108.dsl.austtx.swbell.net x.opn glyph H :0 glyph
        #>> :x.opn 315 glyph glyph :End of /WHO list.
        if not params:
            self.sendMessage(irc.RPL_ENDOFWHO, ":/WHO not supported.")
            return

        try:
            channelOrUser = params[0].decode(self.encoding)
        except __HOLE__:
            self.sendMessage(
                irc.RPL_ENDOFWHO, params[0],
                ":End of /WHO list (could not decode your unicode!)")
            return

        if channelOrUser.startswith('#'):
            def ebGroup(err):
                err.trap(ewords.NoSuchGroup)
                self.sendMessage(
                    irc.RPL_ENDOFWHO, channelOrUser,
                    ":End of /WHO list.")
            d = self.realm.lookupGroup(channelOrUser[1:])
            d.addCallbacks(self._channelWho, ebGroup)
        else:
            def ebUser(err):
                err.trap(ewords.NoSuchUser)
                self.sendMessage(
                    irc.RPL_ENDOFWHO, channelOrUser,
                    ":End of /WHO list.")
            d = self.realm.lookupUser(channelOrUser)
            d.addCallbacks(self._userWho, ebUser)
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/words/service.py/IRCUser.irc_WHO