[enh] better search language selection from query

        modified = False

        if query_parts[0].startswith(':'):

            lang = query_parts[0][1:]

            if lang in (x[0] for x in language_codes):

            for lc in language_codes:

                lang_id, lang_name, country = map(str.lower, lc)

                if lang == lang_id\

                   or lang_id.startswith(lang)\

                   or lang == lang_name\

                   or lang == country:

                    self.lang = lang

                    modified = True

                    break

        elif query_parts[0].startswith('!'):

            prefix = query_parts[0][1:].replace('_', ' ')

            if prefix in engine_shortcuts\

               and not engine_shortcuts[prefix] in self.blocked_engines:

                modified = True