code: func NewClient(httpClient *http.Client, mode, clientID, clientSecret, accessToken string) *Client {
  	b := sling.New().Client(httpClient).Base(baseURL)
  	b.QueryStruct(struct {
  		V            string `url:"v"`
  		M            string `url:"m"`
  		ClientID     string `url:"client_id"`
  		ClientSecret string `url:"client_secret,omitempty"`
  		AccessToken  string `url:"access_token,omitempty"`
  	}{
  		V:            version,
  		M:            mode,
  		ClientID:     clientID,
  		ClientSecret: clientSecret,
  		AccessToken:  accessToken,
  	})
  
  	return &Client{
  		sling:  b,
  		Venues: newVenueService(b.New()),
  	}
  }
docs: // NewClient returns a new Client.