python编程从入门到实践17章使用API；17.3Hacker News API的调用

https://hacker-news.firebaseio.com/v0/topstories.json，但是我打不开，要翻墙吗。抄的程序

import requests
from operator import itemgetter
import pygal
from pygal.style import LightenStyle as LS

# 执行API调用并存储响应
url = 'https://hacker-news.firebaseio.com/v0/topstories.json'
r = requests.get(url)
print("Status code:", r.status_code)

# 处理有关每篇文章的信息
submission_ids = r.json()
submission_dicts = []
for submission_id in submission_ids[:30]:
    # 对于每篇文章，都执行一个API调用
    url = ('https://hacker-news.firebaseio.com/v0/item/' +
           str(submission_id) + '.json')
    submission_r = requests.get(url)
    # print(submission_r.status_code)
    response_dict = submission_r.json()
    submission_dict = {
        'label': response_dict['title'],
        'xlink': 'http://news.ycombinator.com/item?id=' + str(submission_id),
        'value': response_dict.get('descendants', 0)
    }
    submission_dicts.append(submission_dict)

# submission_dicts = sorted(submission_dicts, key=itemgetter('comments'),reverse=True)

# for submission_dict in submission_dicts:
#     print("\nTitle:",submission_dict['title'])
#     print("Discussion link:",submission_dict['link'])
#     print("Comments:",submission_dict['comments'])


# 绘制条形图显示Hacker News上当前最活跃的讨论
my_style = LS('#333366')
my_config = pygal.Config()
my_config.x_label_rotation = 45
my_config.show_legend = False
my_config.truncate_label = 15
my_config.title_font_size = 24
my_config.label_font_size = 14
my_config.major_label_font_size = 18
my_config.show_y_guides = False
chart = pygal.Bar(my_config, style=my_style)
chart.title = "Most-active news on Hacker News"


chart.add('', submission_dicts)
chart.render_to_file('news.svg')