code: function buildApplyForDelegate(address, url) {
    var contract = new WitnessCreateContract();
  
    contract.setOwnerAddress(Uint8Array.from(decode58Check(address)));
    contract.setUrl(encodeString(url));
  
    return buildTransferContract(
      contract,
      Transaction.Contract.ContractType.WITNESSCREATECONTRACT,
      "WitnessCreateContract");
  }
docs: Unfreeze balance
  
  @param address From which address to freze
  @param url url