Extract asset tags from text into a convenient form.

        @param text: Text to extract asset tags from. This text contains HTML
            code that is parsed by BeautifulSoup.
        @type text: str

        @return: Asset map.
        @rtype: {
            '<id>': {
                'name': '<name>',
                'extension': '<extension>'
            },
            ...
        }

def _extract_asset_tags(self, text):
        """
        Extract asset tags from text into a convenient form.

        @param text: Text to extract asset tags from. This text contains HTML
            code that is parsed by BeautifulSoup.
        @type text: str

        @return: Asset map.
        @rtype: {
            '<id>': {
                'name': '<name>',
                'extension': '<extension>'
            },
            ...
        }
        """
        soup = BeautifulSoup(text)
        asset_tags_map = {}

        for asset in soup.find_all('asset'):
            asset_tags_map[asset['id']] = {'name': asset['name'],
                                           'extension': asset['extension']}

        return asset_tags_map