code: public ChangeRequest getChangeRequest(
        String changeRequestId, Dns.ChangeRequestOption... options) {
      checkNotNull(changeRequestId);
      return dns.getChangeRequest(getName(), changeRequestId, options);
    }
docs: Retrieves an updated information about a change request previously submitted to be applied to
  this zone. Returns a {@link ChangeRequest} or {@code null} if the change request was not found.
  Throws {@link DnsException} if the zone is not found.
  
  @param options optional restriction on what fields of {@link ChangeRequest} should be returned
  @return updated ChangeRequest
  @throws DnsException upon failure or if the zone is not found
  @throws NullPointerException if {@code changeRequestId} is null