How to use the urlscan.urlscan.Chunk function in urlscan

if data:
            if data[0].isspace():
                self.trailing_space = True
            if data[-1].isspace():
                future_trailing_space = True
        data = ' '.join(data.split())
        if self.anchor_stack[-1] is None:
            style = 'msgtext'
        else:
            style = 'anchor'
        if self.style_stack[-1]:
            stylelist = list(self.style_stack[-1])
            stylelist.sort()
            style = style + ':' + ''.join(stylelist)

        self.add_chunk(Chunk((style, data), self.cur_url()))
        self.trailing_space = future_trailing_space

def end_para(self):
        if self.at_para_start:
            self.rval.append([])
        else:
            self.at_para_start = True
        self.trailing_space = False
        if self.list_stack:
            self.add_chunk(Chunk(' ' * 3 * len(self.list_stack),
                                 self.cur_url()))

def end_list_para(self):
        if self.at_para_start:
            self.rval.append([])
        if self.list_stack:
            tag = self.list_stack[-1][0]
            if tag == 'ul':
                depth = len([t for t in self.list_stack if t[0] == tag])
                ul_tags = HTMLChunker.ul_tags
                chunk = Chunk('%s  ' % (ul_tags[depth % len(ul_tags)]),
                              self.cur_url())
            else:
                counter = self.list_stack[-1][1]
                self.list_stack[-1] = (tag, counter + 1)
                chunk = Chunk("%2d." % counter, self.cur_url())
            self.add_chunk(chunk)
        else:
            self.end_para()

loc = 0

    for match in URLRE.finditer(mesg):
        if loc < match.start():
            rval.append(Chunk(mesg[loc:match.start()], None))
        # Turn email addresses into mailto: links
        email = match.group("email")
        if email and "mailto" not in email:
            mailto = "mailto:{}".format(email)
        else:
            mailto = match.group(1)
        rval.append(Chunk(None, mailto))
        loc = match.end()

    if loc < len(mesg):
        rval.append(Chunk(mesg[loc:], None))

    return rval

def add_chunk(self, chunk):
        if self.at_para_start:
            self.rval.append([])
        elif self.trailing_space:
            self.rval[-1].append(Chunk(' ', self.cur_url()))

        self.rval[-1].append(chunk)
        self.at_para_start = False
        self.trailing_space = False

components."""

    rval = []

    loc = 0

    for match in URLRE.finditer(mesg):
        if loc < match.start():
            rval.append(Chunk(mesg[loc:match.start()], None))
        # Turn email addresses into mailto: links
        email = match.group("email")
        if email and "mailto" not in email:
            mailto = "mailto:{}".format(email)
        else:
            mailto = match.group(1)
        rval.append(Chunk(None, mailto))
        loc = match.end()

    if loc < len(mesg):
        rval.append(Chunk(mesg[loc:], None))

    return rval