code: func RegisterAztec(pdf barcodePdf, code string, minECCPercent int, userSpecifiedLayers int) string {
  	bcode, err := aztec.Encode([]byte(code), minECCPercent, userSpecifiedLayers)
  	return registerBarcode(pdf, bcode, err)
  }
docs: // RegisterAztec registers a barcode of type Aztec to the PDF, but not to
  // the page. Use Barcode() with the return value to put the barcode on the page.
  // code is the string to be encoded. minECCPercent is the error correction percentage. 33 is the default.
  // userSpecifiedLayers can be a value between -4 and 32 inclusive.