Error undefined: imagick.Initialize while using imagick

I am using the gopkg.in/gographics/imagick.v2/imagick package but it shows the error while running the server : undefined: imagick.Initialize

import "gopkg.in/gographics/imagick.v2/imagick"
func ConvertPdfToJpg() {
    imagick.Initialize()
    defer imagick.Terminate()
    mw := imagick.NewMagickWand()
    defer mw.Destroy()
    mw.ReadImage("test.pdf")
    mw.SetIteratorIndex(0)
    mw.SetImageFormat("jpg")
    mw.WriteImage("test.jpg")
}