code: def __get_sound(self, surah, ayah):
          
          # Formatting ayah with 0 leading.
          # http://stackoverflow.com/questions/17118071/python-add-leading-zeroes-using-str-format
          format_ayah = '{0:0>3}'.format(ayah)
          sound_url = '{base}/sounds/{surah}/{ayah}.mp3'.format(
              base=self.BASE_API, surah=surah, ayah=format_ayah
          )
          return sound_url
docs: Perform http request to get sound from given surah and ayah.
  
          Parameter:
              :surah      --  Surah index from API pages.
              :ayat       --  Ayat key.
  
          Return:
              :string     --  URL for mp3 sound.