code: function KeyPair(privkey) {
    if (!(this instanceof KeyPair)) {
      return new KeyPair(privkey);
    }
  
    if (privkey) {
      this._keypair = ecdsa.keyFromPrivate(privkey);
    } else {
      this._keypair = ecdsa.genKeyPair();
    }
  }
docs: Creates a ECDSA key pair instance for bridge authentication
  @constructor
  @param {String|Buffer} privkey - Hex encoded ECDSA (secp256k1) public key