如何在Go模板中替换字符串？

我用的是"text/template"模块.

我有像这样的结构来解析Blogger中的XML

type Media struct {
    ThumbnailUrl string `xml:"url,attr"`
}


type Entry struct {
    ID string `xml:"id"`
    Published Date `xml:"published"`
    Updated Date `xml:"updated"`
    Draft Draft `xml:"control>draft"`
    Title string `xml:"title"`
    Content string `xml:"content"`
    Tags Tags `xml:"category"`
    Author Author `xml:"author"`
    Media Media `xml:"thumbnail"`
    Extra string
}

然后我像这样创建Go Template

[image]
    src = "{{ replace .Media.ThumbnailUrl 's72-c' 's1600' }}"
    link = ""
    thumblink = "{{ .Media.ThumbnailUrl }}"
    alt = ""
    title = ""
    author = ""
    license = ""
    licenseLink = ""

替换功能未定义.我想替换来自的URL{{ .Media.ThumbnailUrl }}

例如:

来自此网址

https://2.bp.blogspot.com/-DEeRanrBa6s/WGWGwA2qW5I/AAAAAAAADg4/feGUc-g9rXc9B7hXpKr0ecG9UOMXU3_VQCK4B/s72-c/pemrograman%2Bjavascript%2B-%2Bpetanikode.png

到这个URL

https://2.bp.blogspot.com/-DEeRanrBa6s/WGWGwA2qW5I/AAAAAAAADg4/feGUc-g9rXc9B7hXpKr0ecG9UOMXU3_VQCK4B/s1600/pemrograman%2Bjavascript%2B-%2Bpetanikode.png