parse section to formal format

        raw_content: {title: section(with title)}. For `help` access.

        formal_content: {title: section} but the section has been dedented
        without title. For parse instance

def parse_content(self, text):
        """parse section to formal format

        raw_content: {title: section(with title)}. For `help` access.

        formal_content: {title: section} but the section has been dedented
        without title. For parse instance"""
        raw_content = self.raw_content
        raw_content.clear()
        formal_collect = {}

        with warnings.catch_warnings():
            warnings.simplefilter("ignore")
            try:
                split = self.visible_empty_line_re.split(text)
            except ValueError:  # python >= 3.5
                split = [text]

        option_split_re = self.option_split_re
        name = re.compile(re.escape(self.option_name), re.IGNORECASE)
        for text in filter(lambda x: x and x.strip(), split):

            # logger.warning('get options group:\n%r', text)
            with warnings.catch_warnings():
                warnings.simplefilter("ignore")
                try:
                    split_options = option_split_re.split(text)
                except ValueError:  # python >= 3.5
                    continue

            split_options.pop(0)

            for title, section in zip(split_options[::2], split_options[1::2]):
                prefix, end = name.split(title)

                prefix = prefix.strip()

                section = section.rstrip()
                if end.endswith('\n'):
                    formal = section
                else:
                    formal = ' ' * len(title) + section

                formal_collect.setdefault(prefix, []).append(formal)

                # logger.error((title, section))
                if prefix in raw_content:
                    # TODO: better handling way?
                    if self.namedoptions:
                        log = logger.warning
                    else:
                        log = logger.debug
                    log('duplicated options section %s', prefix)

                    raw_content[prefix] += '\n%s%s' % (title, section)
                else:
                    raw_content[prefix] = title + section

        if formal_collect:
            for each_title, values in formal_collect.items():
                value = '\n'.join(map(textwrap.dedent, values))
                formal_collect[each_title] = value

        self.formal_content = formal_collect