code: func (r *EchoResponse) SimpleCard(title string, content string) *EchoResponse {
  	r.Response.Card = &EchoRespPayload{
  		Type:    "Simple",
  		Title:   title,
  		Content: content,
  	}
  
  	return r
  }
docs: // SimpleCard will indicate that a card should be included in the Alexa companion app as part of the response.
  // The card will be shown with the provided title and content.