How to use the pytube.extract.get_vid_descr function in pytube

def test_get_vid_desc(cipher_signature):
    expected = "PSY - DADDY(feat. CL of 2NE1) M/V @ https://youtu.be/FrG4TEcSuRgPSY - 나팔바지(NAPAL BAJI) M/V @ https://youtu.be/tF27TNC_4pcPSY - 7TH ALBUM '칠집싸이다' on iTunes @ http://smarturl.it/PSY_7THALBUMPSY - GANGNAM STYLE(강남스타일) on iTunes @ http://smarturl.it/PsyGangnam#PSY #싸이 #GANGNAMSTYLE #강남스타일More about PSY@http://www.psypark.com/http://www.youtube.com/officialpsyhttp://www.facebook.com/officialpsyhttp://twitter.com/psy_oppahttps://www.instagram.com/42psy42http://iTunes.com/PSYhttp://sptfy.com/PSYhttp://weibo.com/psyoppahttp://twitter.com/ygent_official"  # noqa
    assert extract.get_vid_descr(cipher_signature.watch_html) == expected

)['args']

			# Fix for KeyError: 'title' issue #434
			if 'title' not in self.player_config_args:
				i_start = (
					self.watch_html
					.lower()
					.index('<title>') + len('&lt;title&gt;')
				)
				i_end = self.watch_html.lower().index('</title>')
				title = self.watch_html[i_start:i_end].strip()
				index = title.lower().rfind(' - youtube')
				title = title[:index] if index &gt; 0 else title
				self.player_config_args['title'] = title

		self.vid_descr = extract.get_vid_descr(self.watch_html)
		# https://github.com/nficano/pytube/issues/165
		stream_maps = ['url_encoded_fmt_stream_map']
		if 'adaptive_fmts' in self.player_config_args:
			stream_maps.append('adaptive_fmts')

		# unscramble the progressive and adaptive stream manifests.
		for fmt in stream_maps:
			if not self.age_restricted and fmt in self.vid_info:
				mixins.apply_descrambler(self.vid_info, fmt)
			mixins.apply_descrambler(self.player_config_args, fmt)

			try:
				mixins.apply_signature(self.player_config_args, fmt, self.js)
			except TypeError:
				self.js_url = extract.js_url(
					self.embed_html, self.age_restricted,

)['args']

            # Fix for KeyError: 'title' issue #434
            if 'title' not in self.player_config_args:
                i_start = (
                    self.watch_html
                    .lower()
                    .index('<title>') + len('&lt;title&gt;')
                )
                i_end = self.watch_html.lower().index('</title>')
                title = self.watch_html[i_start:i_end].strip()
                index = title.lower().rfind(' - youtube')
                title = title[:index] if index &gt; 0 else title
                self.player_config_args['title'] = title

        self.vid_descr = extract.get_vid_descr(self.watch_html)
        # https://github.com/nficano/pytube/issues/165
        stream_maps = ['url_encoded_fmt_stream_map']
        if 'adaptive_fmts' in self.player_config_args:
            stream_maps.append('adaptive_fmts')

        # unscramble the progressive and adaptive stream manifests.
        for fmt in stream_maps:
            if not self.age_restricted and fmt in self.vid_info:
                mixins.apply_descrambler(self.vid_info, fmt)
            mixins.apply_descrambler(self.player_config_args, fmt)

            try:
                mixins.apply_signature(self.player_config_args, fmt, self.js)
            except TypeError:
                self.js_url = extract.js_url(
                    self.embed_html, self.age_restricted,

interstitial step.

        :rtype: None

        """
        logger.info('init started')

        self.vid_info = {k: v for k, v in parse_qsl(self.vid_info)}
        if self.age_restricted:
            self.player_config_args = self.vid_info
        else:
            self.player_config_args = extract.get_ytplayer_config(
                self.watch_html,
            )['args']

        self.vid_descr = extract.get_vid_descr(self.watch_html)
        # https://github.com/nficano/pytube/issues/165
        stream_maps = ['url_encoded_fmt_stream_map']
        if 'adaptive_fmts' in self.player_config_args:
            stream_maps.append('adaptive_fmts')

        # unscramble the progressive and adaptive stream manifests.
        for fmt in stream_maps:
            if not self.age_restricted and fmt in self.vid_info:
                mixins.apply_descrambler(self.vid_info, fmt)
            mixins.apply_descrambler(self.player_config_args, fmt)

            try:
                mixins.apply_signature(self.player_config_args, fmt, self.js)
            except TypeError:
                self.js_url = extract.js_url(
                    self.embed_html, self.age_restricted,