code: func (s *RepositoriesService) GetReadme(ctx context.Context, owner, repo string, opt *RepositoryContentGetOptions) (*RepositoryContent, *Response, error) {
  	u := fmt.Sprintf("repos/%v/%v/readme", owner, repo)
  	u, err := addOptions(u, opt)
  	if err != nil {
  		return nil, nil, err
  	}
  	req, err := s.client.NewRequest("GET", u, nil)
  	if err != nil {
  		return nil, nil, err
  	}
  	readme := new(RepositoryContent)
  	resp, err := s.client.Do(ctx, req, readme)
  	if err != nil {
  		return nil, resp, err
  	}
  	return readme, resp, nil
  }
docs: // GetReadme gets the Readme file for the repository.
  //
  // GitHub API docs: https://developer.github.com/v3/repos/contents/#get-the-readme