check_ical.py

from icalendar import Calendar
import requests
import sys

# print("get ics from url")
# text = requests.get("https://chaotikum.org/events.ics").text

print("get ics from _site/events.ics")
with open("_site/events.ics") as f:
    text = f.read()

try:
    print("read ics")
    c = Calendar.from_ical(text)
except:
    print("ERROR: ical file not valid")
    sys.exit(1)