code: public boolean HasKeyType(CBORObject keyTypeObj) {
          CBORObject thatObj = keyTypeObj;
          CBORObject thisObj = get(KeyKeys.KeyType);
          boolean result;
          if (thatObj == null) {
              result = (thisObj == null);
          } else {
              result = thatObj.equals(thisObj);
          }
          return result;
      }
docs: Compares the key's assigned key type with the provided value, indicating if the values are the
  same.
  
  @param keyTypeObj
  the key type to compare or {@code null} to check for no assignment.
  @return {@code true} if the current key has the provided identifier assigned, or {@code false}
  otherwise