{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"What are the failure handling principles for blockchain upgrading?","a":"Ensure data security:  In case of upgrade failure, it is necessary to ensure that the original chain data is not affected, avoid data loss or tampering, and protect user rights and interests."}]}],"pr":"577821a62c7a9e4f6278b198e5d10de76c8d57c7f5c214389c70f935be834f82"}