Text clients to confirm tomorrow's appointments

from google.oauth2.credentials import Credentials
from googleapiclient.discovery import build
from twilio.rest import Client
import re
from datetime import datetime, timedelta, timezone
from clickruntime import on_trigger, on_event, credentials, http, state

FROM = "+15005550006"

def sms(to, body):
    return Client(credentials.secret("TWILIO_ACCOUNT_SID"), credentials.secret("TWILIO_AUTH_TOKEN")).messages.create(to=to, from_=FROM, body=body)
cal = lambda: build("calendar", "v3", credentials=Credentials(credentials.connection("google", "work")), cache_discovery=False).events()

@on_trigger
def run(event):
    start = (datetime.now(timezone.utc) + timedelta(days=1)).replace(hour=0, minute=0)
    items = cal().list(calendarId="primary", timeMin=start.isoformat(), timeMax=(start + timedelta(days=1)).isoformat(), singleEvents=True).execute()["items"]
    for e in items:
        for phone in re.findall(r"\+\d{8,15}", e.get("description", ""))[:1]:
            sms(phone, f"Reminder: {e['summary']} tomorrow at {e['start']['dateTime'][11:16]}. Reply YES to confirm or NO to cancel.")
            state.set(f"evt:{phone}", e["id"])
    return {"events": len(items)}

@on_event
def handle(event):
    f = event.json or {}
    eid, answer = state.get(f"evt:{f.get('From')}"), (f.get("Body") or "").strip().upper()
    if not eid or answer not in ("YES", "NO"):
        return {"skipped": True}
    label, colour = ("Confirmed", "10") if answer == "YES" else ("Cancelled", "11")
    summary = cal().get(calendarId="primary", eventId=eid).execute()["summary"]
    cal().patch(calendarId="primary", eventId=eid, body={"summary": f"[{label}] {summary}", "colorId": colour}).execute()
    return {"event": eid, "status": label}