code: def search(options = {})
        self.date = options[:date] || date
        self.hd = options[:hd] || hd
        response = HTTParty.get(DEFAULT_URL, query: attributes)
        handle_response(response)
      end
docs: Returns APOD info for specified day.
  
   @see https://api.nasa.gov/api.html#apod
   @rate_limited Yes https://api.nasa.gov/api.html#authentication
   @image_permissions http://apod.nasa.gov/apod/lib/about_apod.html#srapply
   @authentication optional NASA api key https://api.nasa.gov/index.html#apply-for-an-api-key
   @option options [String] :api_key Optional. Uses DEMO_KEY as default.
   @option options [String] :date Optional. Returns the APOD results for
   the given date. Date should be formatted as YYYY-MM-DD. Defaults as today.
   @return [NasaApod::SearchResults] Return APOD post for a specified date.