class_docstr: Class that applies position-dependent phonological transformation
class_docstr_tok: ["Class","that","applies","position-dependent","phonological","transformation"]
docstr: >>> umlaut_a = OldNorsePhonology.phonetic_u_umlaut(a)
  >>> umlaut_a.ipar
  'ø'
  
  >>> umlaut_o = OldNorsePhonology.phonetic_u_umlaut(o)
  >>> umlaut_o.ipar
  'u'
  
  >>> umlaut_e = OldNorsePhonology.phonetic_u_umlaut(e)
  >>> umlaut_e.ipar
  'e'
  
  
  :param sound: vowel
  :return: transformed vowel
docstr_tok: [">",">",">","umlaut_a","=","OldNorsePhonology.phonetic_u_umlaut","(","a",")",">",">",">","umlaut_a.ipar","'","\u00f8'",">",">",">","umlaut_o","=","OldNorsePhonology.phonetic_u_umlaut","(","o",")",">",">",">","umlaut_o.ipar","'","u'",">",">",">","umlaut_e","=","OldNorsePhonology.phonetic_u_umlaut","(","e",")",">",">",">","umlaut_e.ipar","'","e'",":","param","sound",":","vowel",":","return",":","transformed","vowel"]
code: def phonetic_u_umlaut(sound: Vowel) -> Vowel:
      """
      >>> umlaut_a = OldNorsePhonology.phonetic_u_umlaut(a)
      >>> umlaut_a.ipar
      'ø'
  
      >>> umlaut_o = OldNorsePhonology.phonetic_u_umlaut(o)
      >>> umlaut_o.ipar
      'u'
  
      >>> umlaut_e = OldNorsePhonology.phonetic_u_umlaut(e)
      >>> umlaut_e.ipar
      'e'
  
  
      :param sound: vowel
      :return: transformed vowel
      """
      if sound.is_equal(a):
          return oee  # or oe
      elif sound.is_equal(o):
          return u
      else:
          return sound
  
file_path: cltk/src/cltk/phonology/non/transcription.py
imports: from typing import Union
  from cltk.phonology.non.syllabifier import BACK_TO_FRONT_VOWELS
  from cltk.phonology.non.utils import AbstractConsonant, AbstractPosition, Backness, Consonant, Height, Length, Manner, Place, Rank, Rule, Vowel
label_desc: Use image node_id 3 for calling the OldNorsePhonology obj's underlying member method code with example usage: obj.phonetic_u_umlaut(sound) and returns: oee, u, sound