code: func (api *API) CreatePageRule(zoneID string, rule PageRule) (*PageRule, error) {
  	uri := "/zones/" + zoneID + "/pagerules"
  	res, err := api.makeRequest("POST", uri, rule)
  	if err != nil {
  		return nil, errors.Wrap(err, errMakeRequestError)
  	}
  	var r PageRuleDetailResponse
  	err = json.Unmarshal(res, &r)
  	if err != nil {
  		return nil, errors.Wrap(err, errUnmarshalError)
  	}
  	return &r.Result, nil
  }
docs: // CreatePageRule creates a new Page Rule for a zone.
  //
  // API reference: https://api.cloudflare.com/#page-rules-for-a-zone-create-a-page-rule