code: func (p *Provider) Init() error {
  	fm := template.FuncMap{
  		"strsToItfs": func(values []string) []interface{} {
  			var r []interface{}
  			for _, v := range values {
  				r = append(r, v)
  			}
  			return r
  		},
  	}
  
  	defaultRuleTpl, err := provider.MakeDefaultRuleTemplate(p.DefaultRule, fm)
  	if err != nil {
  		return fmt.Errorf("error while parsing default rule: %v", err)
  	}
  
  	p.defaultRuleTpl = defaultRuleTpl
  	return nil
  }
docs: // Init the provider