code: def _expand_alternates(self, phonetic):
          
          alt_start = phonetic.find('(')
          if alt_start == -1:
              return self._normalize_lang_attrs(phonetic, False)
  
          prefix = phonetic[:alt_start]
          alt_start += 1  # get past the (
          alt_end = phonetic.find(')', alt_start)
          alt_string = phonetic[alt_start:alt_end]
          alt_end += 1  # get past the )
          suffix = phonetic[alt_end:]
          alt_array = alt_string.split('|')
          result = ''
  
          for i in range(len(alt_array)):
              alt = alt_array[i]
              alternate = self._expand_alternates(prefix + alt + suffix)
              if alternate != '' and alternate != '[0]':
                  if result != '':
                      result += '|'
                  result += alternate
  
          return result
docs: Expand phonetic alternates separated by |s.
  
          Parameters
          ----------
          phonetic : str
              A Beider-Morse phonetic encoding
  
          Returns
          -------
          str
              A Beider-Morse phonetic code