python3 script to show problem difficulty rating without tags

As I couldn't find any easy way to find problem difficulty rating without seeing tags, I have written a python3 script to do it:

Code

import urllib.request, json

def get_all_problems(contestId):
    query = "https://codeforces.com/api/contest.standings?contestId="+contestId+"&from=1&count=1"
    with urllib.request.urlopen(query) as url:
        data = json.loads(url.read().decode())
        return data['result']['problems']

info = input("Enter contestId[/problemIndex], you can find contestId in URL\n")
if "/" not in info:
    print([(problem['index'], problem.get('rating')) for problem in get_all_problems(info)])
else:
    contestId, problemIndex = info.split('/')
    print([problem.get('rating') for problem in get_all_problems(contestId) if problem['index']==problemIndex][0])

Usage: Run the script. Input the contestId (from URL, e.g. 1148) to view rating of all problems of that contests. Input contestId/problemIndex (e.g. 1108/E2) to view rating of only that problem.

If the problem has no rating yet, it will print None. Exception will be thrown if it fails to connect to codeforces server or invalid input is given.