{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"What are the handling principles for dealing with failed blockchain upgrades?","a":"Rollback and repair: If the upgrade failure causes system problems, timely rollback to the previous version should be performed to  ensure the normal operation of the blockchain. At the same time, analyze the cause of the failure and carry out repairs to avoid the same problem from occurring again."}]}],"pr":"074c65589e7334134b0933a52ed4c3cd14e88f610e8e1c75e148695fc90b282c"}