code: func (cl *Client) GetIAMPolicy(c context.Context, resource string) (*Policy, error) {
  	response := &Policy{}
  	if err := cl.iamAPIRequest(c, resource, "getIamPolicy", nil, response); err != nil {
  		return nil, err
  	}
  	return response, nil
  }
docs: // GetIAMPolicy fetches an IAM policy of a resource.
  //
  // On non-success HTTP status codes returns googleapi.Error.