Go 언어의 시간 기능을 사용하여 일정 달력을 생성하고 PDF 파일로 내보내는 방법은 무엇입니까?

type Event struct {
    Date  time.Time
    Title string
}

func generateEvents(num int) []Event {
    events := make([]Event, num)
    now := time.Now()
    rand.Seed(time.Now().UnixNano())
    for i := 0; i < num; i++ {
        event := Event{
            Date:  now.AddDate(0, 0, rand.Intn(30)),
            Title: fmt.Sprintf("Event %d", i+1),
        }
        events[i] = event
    }
    return events
}

type ByDate []Event

func (b ByDate) Len() int           { return len(b) }
func (b ByDate) Less(i, j int) bool { return b[i].Date.Before(b[j].Date) }
func (b ByDate) Swap(i, j int)      { b[i], b[j] = b[j], b[i] }

func sortEvents(events []Event) {
    sort.Sort(ByDate(events))
}

const (
    pdfWidth  = 210
    pdfHeight = 297
    cellWidth = pdfWidth / 7
    cellHeight = 15
)

func drawCalendar(events []Event) {
    pdf := gofpdf.New("P", "mm", "A4", "")
    pdf.AddPage()
    pdf.SetFont("Arial", "", 12)

    // Draw header
    pdf.CellFormat(pdfWidth, cellHeight, "Calendar", "0", 1, "CM")

    // Draw days of the week
    weekdays := []string{"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"}
    for _, day := range weekdays {
        pdf.CellFormat(cellWidth, cellHeight, day, "1", 0, "CM", false, 0, "")
    }
    pdf.Ln(-1)

    // Draw events
    for _, event := range events {
        day := event.Date.Weekday()
        x := float64(day) * cellWidth
        y := pdf.GetY()

        pdf.SetX(x)
        pdf.SetY(y)
        pdf.CellFormat(cellWidth, cellHeight, event.Title, "1", 0, "CM", false, 0, "")

        pdf.Ln(-1)
    }

    pdf.OutputFileAndClose("calendar.pdf")
}

func main() {
    events := generateEvents(10)
    sortEvents(events)
    drawCalendar(events)
}