Detect Fraud by Propagating Suspicious PII

Implement classify_fraud_events(events: list[dict]) -> list[str]. You are given a list of events. Each event has an event_type equal to either "underwriting" or "fraud_flag". Its customer_details may contain any combination of the fields address, phone, email, and ssn. If customer_details is absent or null, treat it as providing no values. A field contributes a value only when the value is a string and is not "". Maintain one global suspicious set. A fraud_flag event adds…