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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def decompose_nfkd(text):
 """Perform unicode compatibility decomposition. This will replace some non-standard value representations in unicode and normalise them, while also separating characters and their diacritics into two separate codepoints. """

    if text is None:
        return None
    if not hasattr(decompose_nfkd, '_tr'):
        decompose_nfkd._tr = Transliterator.createInstance('Any-NFKD')
    return decompose_nfkd._tr.transliterate(text)