human
Solve the following python programming problem given the following code:
@ classmethod 
def normalize_vi(cls, text) : 
    'Normalizer for Vietnamese.
        Normalize Alphabet + Diacritical Mark(U+03xx) into U+1Exx.
        ' 
    def repl(m) : 
        alphabet = cls.TO_NORMALIZE_VI_CHARS.find (m.group (1)) 
        dmark = cls.DMARK_CLASS.find (m.group (2)) 
        return cls.NORMALIZED_VI_CHARS [dmark] [alphabet] 
return cls.ALPHABET_WITH_DMARK.sub (cls, text) 

    
    

    Fix the buggy line: return cls.ALPHABET_WITH_DMARK.sub (cls, text)
assistant
#Here is Python code to find (m.

return cls.ALPHABET_WITH_DMARK.sub (def repl(, text)