code: def _parse_ipa_syllable(unparsed_syllable):
      
      ipa_tone = re.search('[%(marks)s]+' % {'marks': _IPA_MARKS},
                           unparsed_syllable)
      if not ipa_tone:
          syllable, tone = unparsed_syllable, '5'
      else:
          for tone_number, tone_mark in _IPA_TONES.items():
              if ipa_tone.group() == tone_mark:
                  tone = tone_number
                  break
          syllable = unparsed_syllable[0:ipa_tone.start()]
      return syllable, tone
docs: Return the syllable and tone of an IPA syllable.