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In wake of last week ’s ransomware attack , technology specialists warn that ‘ paying money to a criminal is never a good idea ’ Cybersecurity experts have warned businesses against meeting hackers ’ demands for money in the wake of the “ unprecedented ” attack on hundreds of thousands of computer systems around the world .
 ( ransom: demands for money,  businesses: victim, 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: demands for money,  businesses: victim, hackers: attacker) 