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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __stringlist(self, ttype, tvalue):
 """Specific method to parse the 'string-list' type Syntax: string-list = "[" string *("," string) "]" / string ; if there is only a single string, the brackets ; are optional """

        if ttype == "string":
            self.__curstringlist += [tvalue.decode("utf-8")]
            self.__set_expected("comma", "right_bracket")
            return True
        if ttype == "comma":
            self.__set_expected("string")
            return True
        if ttype == "right_bracket":
            self.__curcommand.check_next_arg("stringlist", self.__curstringlist)
            self.__cstate = self.__arguments
            return self.__check_command_completion()
        return False