code: func (c *conferencePageIterator) Next(ctx context.Context) (*ConferencePage, error) {
  	cp := new(ConferencePage)
  	err := c.p.Next(ctx, cp)
  	if err != nil {
  		return nil, err
  	}
  	c.p.SetNextPageURI(cp.NextPageURI)
  	return cp, nil
  }
docs: // Next returns the next page of resources. If there are no more resources,
  // NoMoreResults is returned.