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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 tokenize(text, lowercase=False, deacc=False):
 """ Iteratively yield tokens as unicode strings, optionally also lowercasing them and removing accent marks. """

    if lowercase:
        text = text.lower()
    if deacc:
        text = deaccent(text)
    for match in PAT_ALPHABETIC.finditer(text):
        yield match.group()