Parser

#!/usr/local/bin/python3
# -*- coding: utf-8 -*-
# [email protected] - CS

from html.parser import HTMLParser
from urllib.request import quote, urlopen


class Parser(HTMLParser):
    """Helper class for retrieving header."""

    def __init__(self):
        HTMLParser.__init__(self)
        self.in_head_tag = False
        self.in_span_tag = False
        self.head_text = ''

    def handle_starttag(self, tag, attrs):
        if tag == 'h1':
            attrs = dict(attrs)
            if 'id' in attrs and attrs['id'] == 'firstHeading':
                self.in_head_tag = True
        if self.in_head_tag and tag == 'span':
            self.in_span_tag = True

    def handle_endtag(self, tag):
        if self.in_head_tag and tag == 'h1':
            self.in_head_tag = False
        if self.in_span_tag and tag == 'span':
            self.in_span_tag = False

    def handle_data(self, data):
        if self.in_span_tag:
            self.head_text = data

    def parse(self, page):
        """Return text of article."""

        self.feed(page)
        return self.head_text


WIKI_ROOT = 'http://wiki.cs.hse.ru/'

def load(name):
    """Return text of the article with specified url."""

    with urlopen(WIKI_ROOT + quote(name)) as file:
        page = str(file.read(), encoding='utf-8')
    return page


def get_head(page):
    """Return head of page."""

    return Parser().parse(page)


def main():
    page = load('Рекомендательная_система_(семинар)')
    print('Заголовок: "{head}"'.format(head = get_head(page)))


if __name__ == '__main__':
    main()