code: func MarkdownHelper(body string, help HelperContext) (template.HTML, error) {
  	var err error
  	if help.HasBlock() {
  		body, err = help.Block()
  		if err != nil {
  			return "", err
  		}
  	}
  	b := github_flavored_markdown.Markdown([]byte(body))
  	return template.HTML(b), err
  }
docs: // Markdown converts the string into HTML using GitHub flavored markdown.