code: func NewGetCFilterHeaderCmd(hash string,
  	filterType wire.FilterType) *GetCFilterHeaderCmd {
  	return &GetCFilterHeaderCmd{
  		Hash:       hash,
  		FilterType: filterType,
  	}
  }
docs: // NewGetCFilterHeaderCmd returns a new instance which can be used to issue a
  // getcfilterheader JSON-RPC command.