Catch chats no agent answered

from datetime import datetime, timedelta, timezone
from clickruntime import on_trigger, credentials, http, state, notify, report_fetched

@on_trigger
def run(event):
    since = (datetime.now(timezone.utc) - timedelta(hours=1)).strftime("%Y-%m-%dT%H:%M:%S.000000Z")
    chats = http.post("https://api.livechatinc.com/v3.5/agent/action/list_archives",
                      json={"filters": {"from": since}, "limit": 100},
                      headers={"Authorization": f"Bearer {credentials.connection('livechat', 'work')}"}).json()["chats"]
    seen = set(state.get("seen") or [])
    missed = []
    for c in chats:
        agents = {u["id"] for u in c["users"] if u["type"] == "agent"}
        replied = any(e.get("author_id") in agents for e in c["thread"]["events"] if e["type"] == "message")
        if not replied and c["id"] not in seen:
            missed.append(c)
    report_fetched(len(missed))
    if not missed:
        return {"summary": "Nothing new"}
    lines = [f"{c['thread']['created_at'][11:16]}  " +
             next((u.get("email", "no email") for u in c["users"] if u["type"] == "customer"), "no email") for c in missed]
    notify.email_me(f"{len(missed)} LiveChat chat(s) got no reply", "\n".join(lines))
    state.set("seen", list(seen | {c["id"] for c in missed})[-500:])
    return {"missed": len(missed)}