docs: def analyze_sequence(ipa):
      """
      Convert a normal ipa string into a prostring for Chinese dialects.
      """
      # we need some very good strategy here, which should be lightwayt and easy
      # to re-implement in other languages (e.g. JS)
  
      # get sound-class rep of stirng first
      seqs = re.split('([₁₂₃₄₅₆₀¹²³⁴⁵⁶⁰])+', ipa)
      out = ''
      for i in range(len(seqs)):
          seqs = ipa2tokens(tokens2class(ipa, merge_vowels=False, expand_nasals=True),'asjp')
      
          D = {}
  
          pass