code: function changeAddrFromMnemonic(mnemonic) {
    // root seed buffer
    const rootSeed = Wormhole.Mnemonic.toSeed(mnemonic)
  
    // master HDNode
    let masterHDNode
    if (NETWORK === "testnet")
      masterHDNode = Wormhole.HDNode.fromSeed(rootSeed, "testnet")
    else masterHDNode = Wormhole.HDNode.fromSeed(rootSeed)
  
    // HDNode of BIP44 account
    const account = Wormhole.HDNode.derivePath(masterHDNode, "m/44'/145'/0'")
  
    // derive the first external change address HDNode which is going to spend utxo
    const change = Wormhole.HDNode.derivePath(account, "0/0")
  
    return change
  }
docs: Generate a change address from a Mnemonic of a private key.