Joeven — Learn Autonomous AI Agents

Python loads on first run

import hashlib
import json

INVOICES = {"INV-17": {"cents": 4000, "refunded": False, "receipt": None}}

def refund(invoice_id, amount_cents):
    inv = INVOICES.get(invoice_id)
    if inv is None:
        return {"error": "not_found", "invoice_id": invoice_id}
    if amount_cents != inv["cents"]:
        return {
            "error": "invalid_args",
            "hint": "amount_cents must match invoice",
            "expected": inv["cents"],
        }
    if inv["refunded"]:
        return {"ok": True, "idempotent": True, "receipt": inv["receipt"]}
    receipt = hashlib.sha256(invoice_id.encode()).hexdigest()[:12]
    inv["refunded"] = True
    inv["receipt"] = receipt
    return {"ok": True, "idempotent": False, "receipt": receipt}

print("first:", json.dumps(refund("INV-17", 4000)))
print("retry:", json.dumps(refund("INV-17", 4000)))
print("bad amount:", json.dumps(refund("INV-17", 1)))
print("missing:", json.dumps(refund("INV-0", 1)))
print("still one receipt", INVOICES["INV-17"]["receipt"])

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