How can I add a table to a placeholder table? about unioffice HOT 8 CLOSED

// Copyright UniDoc ehf. All rights reserved.
package main

import (
	"fmt"
	"log"
	"os"

	"github.com/unidoc/unioffice/common/license"
	"github.com/unidoc/unioffice/measurement"
	"github.com/unidoc/unioffice/presentation"
	"github.com/unidoc/unioffice/schema/soo/dml"
	"github.com/unidoc/unioffice/schema/soo/pml"
)

func init() {
	// Make sure to load your metered License API key prior to using the library.
	// If you need a key, you can sign up and create a free one at https://cloud.unidoc.io
	err := license.SetMeteredKey(os.Getenv(`UNIDOC_LICENSE_API_KEY`))
	if err != nil {
		panic(err)
	}
}

func main() {
	ppt, err := presentation.Open("placeholder.pptx")
	if err != nil {
		panic(err)
	}
	defer ppt.Close()

	slides := ppt.Slides()
	for _, slide := range slides {
		placeholders := slide.PlaceHolders()
		for _, ph := range placeholders {
			// Add table into placeholder that having type table placeholder.
			if ph.Type() == pml.ST_PlaceholderTypeTbl {
				tbl := ph.AddTable()

				for ci := 0; ci < 4; ci++ {
					col := tbl.AddCol()
					col.SetWidth(measurement.Millimeter * 52)
				}
				for ri := 0; ri < 3; ri++ {
					row := tbl.AddRow()
					row.SetHeight(measurement.Inch)
					for ci, cell := range row.Cells() {
						cell.TxBody = dml.NewCT_TextBody()

						para := dml.NewCT_TextParagraph()
						cell.TxBody.P = append(cell.TxBody.P, para)

						egtr := dml.NewEG_TextRun()
						para.EG_TextRun = append(para.EG_TextRun, egtr)
						egtr.R = dml.NewCT_RegularTextRun()
						egtr.R.T = fmt.Sprintf("Cell %d:%d", ri, ci)
					}
				}

				style := dml.NewCT_TableStyle()
				style.WholeTbl = dml.NewCT_TablePartStyle()
				tcStyle := dml.NewCT_TableStyleCellStyle()
				tcStyle.Fill = dml.NewCT_FillProperties()
				tcStyle.Fill.SolidFill = dml.NewCT_SolidColorFillProperties()
				tcStyle.Fill.SolidFill.SrgbClr = dml.NewCT_SRgbColor()
				tcStyle.Fill.SolidFill.SrgbClr.ValAttr = "FF9900"
				style.WholeTbl.TcStyle = tcStyle
				tbl.SetStyle(style)

				tbl.SetOffsetX(measurement.Inch)
				tbl.SetOffsetY(measurement.Millimeter * 20)

				// Remove placeholder after the table being added.
				err := ph.Remove()
				if err != nil {
					log.Fatal(err)
				}
			}
		}
	}

	ppt.SaveToFile("result.pptx")
}