package main import ( "fmt" "github.com/ethereum/go-ethereum/core/types" ) func main() { block := types.NewBlock(&types.Header{ ParentHash: []byte("0x1234567890abcdef"), // other header fields }, nil, nil) fmt.Println("Parent Hash:", block.ParentHash()) }In this example, we create a new Block instance with a dummy header that has a ParentHash value of "0x1234567890abcdef". We then print out the parent hash using the block's ParentHash method. Overall, Block.ParentHash is a useful field for tracking the blockchain's structure and verifying the integrity of blocks. It's part of the go-ethereum.core.types package, which provides a range of other data types and utilities for Ethereum development.