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In the CloudPets incident , different hackers appear to have deleted the original databases , but left ransom notes on the exposed systems , Hunt said .
 ( ransom: left,  ransom notes: tool, the exposed systems: victim, have deleted the original databases: attack pattern, hackers: attacker) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: phishing, data breach, ransom, discover vulnerability, patch vulnerability, Arguments type: vulnerable system, capabilities, vulnerability, number of victim, issues addressed, compromised data, damage amount, common vulnerabilities and exposures, victim, patch number, number of data, tool, discoverer, time, purpose, place, payment method, releaser, vulnerable system version, attacker, supported platform, patch, price, vulnerable system owner, trusted entity, attack pattern. 
Text: {0} 
Answer:
 ( ransom: left,  ransom notes: tool, the exposed systems: victim, have deleted the original databases: attack pattern, hackers: attacker) 