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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 compose_nfc(text):
 """Perform unicode composition."""

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