"""Markets Open: source-linked calendar-date counts, no settlement inference."""
import json
from urllib.request import urlopen

url = (
    "https://marketsopen.today/api/v1/trading-days"
    "?markets=SSE,HKEX,NB,SB&start=2026-10-01&end=2026-10-31"
)
with urlopen(url, timeout=15) as response:
    result = json.load(response)
for market in result["markets"]:
    if market["complete"]:
        print(market["market_id"], market["total"])
    else:
        print(market["market_id"], "incomplete", market["lower"], market["upper"])
    print("Sources:", market["source_urls"])
print("Data version:", result["data_version"])
# None/null is unknown; half days count as one trading day.
# Shared dates are not simultaneous trading windows or settlement dates.