{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"The development history of blockchain is as follows:","a":"Blockchain  2.0 era (2013 to present): With the birth of Ethereum, blockchain technology entered the era of smart contracts."}]}],"pr":"0e2af7ced3a57cfc6d5ea7b685edd014c7537b0d777c1e3f2579b30802bad73f"}