code: func (cl *Client) iamAPIRequest(c context.Context, resource, action string, body, resp interface{}) error {
  	if cl.BasePath != "" {
  		// We are in "testing"
  		base, err := url.Parse(cl.BasePath)
  		if err != nil {
  			return err
  		}
  		return cl.genericAPIRequest(c, base, resource, action, body, resp)
  	}
  	return cl.genericAPIRequest(c, DefaultIamBaseURL, resource, action, body, resp)
  }
docs: // iamAPIRequest performs HTTP POST to the core IAM API endpoint.