How to use the youtube-dl.youtube_dl.utils.float_or_none function in youtube_dl

def _add_chapter(start_time, end_time):
                start_time = float_or_none(start_time, 1000)
                end_time = float_or_none(end_time, 1000)
                if start_time is None or end_time is None:
                    return
                chapters.append({
                    'start_time': start_time,
                    'end_time': end_time,
                })

return
                chapters.append({
                    'start_time': start_time,
                    'end_time': end_time,
                })

            for chapter in tp_chapters[:-1]:
                _add_chapter(chapter.get('startTime'), chapter.get('endTime'))
            _add_chapter(tp_chapters[-1].get('startTime'), tp_chapters[-1].get('endTime') or duration)

        return {
            'title': info['title'],
            'subtitles': subtitles,
            'description': info['description'],
            'thumbnail': info['defaultThumbnailUrl'],
            'duration': float_or_none(duration, 1000),
            'timestamp': int_or_none(info.get('pubDate'), 1000) or None,
            'uploader': info.get('billingCode'),
            'chapters': chapters,
        }

thumbnails = [{
            'id': thumbnail_id,
            'url': thumbnail_url,
            'width': int_or_none(thumbnail_id[1:])
        } for thumbnail_id, thumbnail_url in common_data.get('image', {}).get('sizes', {}).items()]

        return {
            '_type': 'url_transparent',
            'url': smuggle_url(
                self.BRIGHTCOVE_URL_TEMPLATE % brightcove_id,
                {'geo_countries': self._GEO_COUNTRIES}),
            'id': video_id,
            'title': title,
            'description': common_data.get('description'),
            'duration': float_or_none(video_data.get('duration'), 1000),
            'thumbnails': thumbnails,
            'ie_key': 'BrightcoveNew',
        }

break

        formats = []
        rtmp_count = 0
        http_count = 0
        m3u8_count = 0

        srcs = []
        media = smil.findall(self._xpath_ns('.//video', namespace)) + smil.findall(self._xpath_ns('.//audio', namespace))
        for medium in media:
            src = medium.get('src')
            if not src or src in srcs:
                continue
            srcs.append(src)

            bitrate = float_or_none(medium.get('system-bitrate') or medium.get('systemBitrate'), 1000)
            filesize = int_or_none(medium.get('size') or medium.get('fileSize'))
            width = int_or_none(medium.get('width'))
            height = int_or_none(medium.get('height'))
            proto = medium.get('proto')
            ext = medium.get('ext')
            src_ext = determine_ext(src)
            streamer = medium.get('streamer') or base

            if proto == 'rtmp' or streamer.startswith('rtmp'):
                rtmp_count += 1
                formats.append({
                    'url': streamer,
                    'play_path': src,
                    'ext': 'flv',
                    'format_id': 'rtmp-%d' % (rtmp_count if bitrate is None else bitrate),
                    'tbr': bitrate,

def _parse_xspf(self, xspf_doc, playlist_id, xspf_url=None, xspf_base_url=None):
        NS_MAP = {
            'xspf': 'http://xspf.org/ns/0/',
            's1': 'http://static.streamone.nl/player/ns/0',
        }

        entries = []
        for track in xspf_doc.findall(xpath_with_ns('./xspf:trackList/xspf:track', NS_MAP)):
            title = xpath_text(
                track, xpath_with_ns('./xspf:title', NS_MAP), 'title', default=playlist_id)
            description = xpath_text(
                track, xpath_with_ns('./xspf:annotation', NS_MAP), 'description')
            thumbnail = xpath_text(
                track, xpath_with_ns('./xspf:image', NS_MAP), 'thumbnail')
            duration = float_or_none(
                xpath_text(track, xpath_with_ns('./xspf:duration', NS_MAP), 'duration'), 1000)

            formats = []
            for location in track.findall(xpath_with_ns('./xspf:location', NS_MAP)):
                format_url = urljoin(xspf_base_url, location.text)
                if not format_url:
                    continue
                formats.append({
                    'url': format_url,
                    'manifest_url': xspf_url,
                    'format_id': location.get(xpath_with_ns('s1:label', NS_MAP)),
                    'width': int_or_none(location.get(xpath_with_ns('s1:width', NS_MAP))),
                    'height': int_or_none(location.get(xpath_with_ns('s1:height', NS_MAP))),
                })
            self._sort_formats(formats)

if not mpd_base_url.endswith('/') and not base_url.startswith('/'):
                                mpd_base_url += '/'
                            base_url = mpd_base_url + base_url
                        representation_id = representation_attrib.get('id')
                        lang = representation_attrib.get('lang')
                        url_el = representation.find(_add_ns('BaseURL'))
                        filesize = int_or_none(url_el.attrib.get('{http://youtube.com/yt/2012/10/10}contentLength') if url_el is not None else None)
                        bandwidth = int_or_none(representation_attrib.get('bandwidth'))
                        f = {
                            'format_id': '%s-%s' % (mpd_id, representation_id) if mpd_id else representation_id,
                            'url': base_url,
                            'manifest_url': mpd_url,
                            'ext': mimetype2ext(mime_type),
                            'width': int_or_none(representation_attrib.get('width')),
                            'height': int_or_none(representation_attrib.get('height')),
                            'tbr': float_or_none(bandwidth, 1000),
                            'asr': int_or_none(representation_attrib.get('audioSamplingRate')),
                            'fps': int_or_none(representation_attrib.get('frameRate')),
                            'language': lang if lang not in ('mul', 'und', 'zxx', 'mis') else None,
                            'format_note': 'DASH %s' % content_type,
                            'filesize': filesize,
                            'container': mimetype2ext(mime_type) + '_dash',
                        }
                        f.update(parse_codecs(representation_attrib.get('codecs')))
                        representation_ms_info = extract_multisegment_info(representation, adaption_set_ms_info)

                        def prepare_template(template_name, identifiers):
                            t = representation_ms_info[template_name]
                            t = t.replace('$RepresentationID$', representation_id)
                            t = re.sub(r'\$(%s)\$' % '|'.join(identifiers), r'%(\1)d', t)
                            t = re.sub(r'\$(%s)%%([^$]+)\$' % '|'.join(identifiers), r'%(\1)\2', t)
                            t.replace('$$', '$')

webpage = self._download_webpage(url, video_id)
        vidplayer_id = self._search_regex(
            r' id="vidplayer([0-9]+)"', webpage, 'internal video ID')

        png_url = 'http://www.rtve.es/ztnr/movil/thumbnail/default/videos/%s.png' % vidplayer_id
        png = self._download_webpage(png_url, video_id, 'Downloading url information')
        video_url = _decrypt_url(png)

        return {
            'id': video_id,
            'ext': 'mp4',
            'title': info['title'],
            'url': video_url,
            'thumbnail': info.get('image'),
            'duration': float_or_none(info.get('duration'), scale=1000),
        }

if m3u8_id:
                    format_id.append(m3u8_id)
                stream_name = build_stream_name()
                # Bandwidth of live streams may differ over time thus making
                # format_id unpredictable. So it's better to keep provided
                # format_id intact.
                if not live:
                    format_id.append(stream_name if stream_name else '%d' % (tbr if tbr else len(formats)))
                manifest_url = format_url(line.strip())
                f = {
                    'format_id': '-'.join(format_id),
                    'url': manifest_url,
                    'manifest_url': m3u8_url,
                    'tbr': tbr,
                    'ext': ext,
                    'fps': float_or_none(last_stream_inf.get('FRAME-RATE')),
                    'protocol': entry_protocol,
                    'preference': preference,
                }
                resolution = last_stream_inf.get('RESOLUTION')
                if resolution:
                    mobj = re.search(r'(?P\d+)[xX](?P\d+)', resolution)
                    if mobj:
                        f['width'] = int(mobj.group('width'))
                        f['height'] = int(mobj.group('height'))
                # Unified Streaming Platform
                mobj = re.search(
                    r'audio.*?(?:%3D|=)(\d+)(?:-video.*?(?:%3D|=)(\d+))?', f['url'])
                if mobj:
                    abr, vbr = mobj.groups()
                    abr, vbr = float_or_none(abr, 1000), float_or_none(vbr, 1000)
                    f.update({

return
            stream_group = groups.get(stream_group_id)
            if not stream_group:
                return stream_group_id
            rendition = stream_group[0]
            return rendition.get('NAME') or stream_group_id

        for line in m3u8_doc.splitlines():
            if line.startswith('#EXT-X-STREAM-INF:'):
                last_stream_inf = parse_m3u8_attributes(line)
            elif line.startswith('#EXT-X-MEDIA:'):
                extract_media(line)
            elif line.startswith('#') or not line.strip():
                continue
            else:
                tbr = float_or_none(
                    last_stream_inf.get('AVERAGE-BANDWIDTH') or
                    last_stream_inf.get('BANDWIDTH'), scale=1000)
                format_id = []
                if m3u8_id:
                    format_id.append(m3u8_id)
                stream_name = build_stream_name()
                # Bandwidth of live streams may differ over time thus making
                # format_id unpredictable. So it's better to keep provided
                # format_id intact.
                if not live:
                    format_id.append(stream_name if stream_name else '%d' % (tbr if tbr else len(formats)))
                manifest_url = format_url(line.strip())
                f = {
                    'format_id': '-'.join(format_id),
                    'url': manifest_url,
                    'manifest_url': m3u8_url,

def _add_chapter(start_time, end_time):
                start_time = float_or_none(start_time, 1000)
                end_time = float_or_none(end_time, 1000)
                if start_time is None or end_time is None:
                    return
                chapters.append({
                    'start_time': start_time,
                    'end_time': end_time,
                })