code: func (s *ReactionsService) ListTeamDiscussionReactions(ctx context.Context, teamID int64, discussionNumber int, opt *ListOptions) ([]*Reaction, *Response, error) {
  	u := fmt.Sprintf("teams/%v/discussions/%v/reactions", teamID, discussionNumber)
  	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
  	}
  
  	req.Header.Set("Accept", mediaTypeReactionsPreview)
  
  	var m []*Reaction
  	resp, err := s.client.Do(ctx, req, &m)
  	if err != nil {
  		return nil, resp, err
  	}
  
  	return m, resp, nil
  }
docs: // ListTeamDiscussionReactions lists the reactions for a team discussion.
  //
  // GitHub API docs: https://developer.github.com/v3/reactions/#list-reactions-for-a-team-discussion