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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 parse(self, text):
 """The parser entry point. Parse the provided text to check for its validity. On success, the parsing tree is available into the result attribute. It is a list of sievecommands.Command objects (see the module documentation for specific information). On error, an string containing the explicit reason is available into the error attribute. :param text: a string containing the data to parse :return: True on success (no error detected), False otherwise """

        if isinstance(text, text_type):
            text = text.encode("utf-8")

        self.__reset_parser()
        try:
            for ttype, tvalue in self.lexer.scan(text):
                if ttype == "hash_comment":
                    self.hash_comments += [tvalue.strip()]
                    continue
                if ttype == "bracket_comment":
                    continue
                if self.__expected is not None:
                    if ttype not in self.__expected:
                        if self.lexer.pos < len(text):
                            msg = (
                                "%s found while %s expected near '%s'"
                                % (ttype, "|".join(self.__expected),
                                   text[self.lexer.pos])
                            )
                        else:
                            msg = (
                                "%s found while %s expected at end of file"
                                  % (ttype, "|".join(self.__expected))
                            )
                        raise ParseError(msg)
                    self.__expected = None

                if not self.__command(ttype, tvalue):
                    msg = (
                        "unexpected token '%s' found near '%s'"
                        % (tvalue.decode(), text.decode()[self.lexer.pos])
                    )
                    raise ParseError(msg)
            if self.__opened_blocks:
                self.__set_expected("right_cbracket")
            if self.__expected is not None:
                raise ParseError("end of script reached while %s expected" %
                                 "|".join(self.__expected))

        except (ParseError, CommandError) as e:
            self.error = "line %d: %s" % (self.lexer.curlineno(), str(e))
            return False
        return True