How to use the sumy.parsers.html.HtmlParser.from_url function in sumy

def get_summary_lex_rank(self,num_sentence):
        from sumy.parsers.plaintext import PlaintextParser  # other parsers available for HTML etc.
        from sumy.nlp.tokenizers import Tokenizer
        from sumy.summarizers.lex_rank import LexRankSummarizer  # We're choosing Lexrank, other algorithms are also built in

        try:
            parser = HtmlParser.from_url(self.url, Tokenizer("english"))
        except:
            try:
                parser = PlaintextParser.from_string(self.body, Tokenizer("english"))
            except Exception as e:
                raise(e)

        summarizer = LexRankSummarizer()
        summary = summarizer(parser.document, num_sentence)
        out=''
        for sentence in summary:
            out+= str(sentence)
        return out

def get_summary(self,num_sentence):
        out = ''
        try:
            try:
                parser = HtmlParser.from_url(self.url, Tokenizer("english"))
            except:
                try:
                    parser = PlaintextParser.from_string(self.body, Tokenizer("english"))
                except Exception as e:
                    raise(e)

            stemmer = Stemmer('english')
            summarizer = Summarizer(stemmer)
            summarizer.stop_words = get_stop_words('english')

            for sentence in summarizer(parser.document, num_sentence):
                out+=str(sentence)
        except:
            return self.body

        return out