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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, encoding='utf8', errors="strict", to_lower=False, lower=False):
 """ Iteratively yield tokens as unicode strings, removing accent marks and optionally lowercasing the unidoce string by assigning True to one of the parameters, lowercase, to_lower, or lower. Input text may be either unicode or utf8-encoded byte string. The tokens on output are maximal contiguous sequences of alphabetic characters (no digits!). [u'Nic', u'nemuze', u'letet', u'rychlosti', u'vyssi', u'nez', u'tisic', u'kilometru', u'za', u'sekundu'] """

    lowercase = lowercase or to_lower or lower
    text = to_unicode(text, encoding, errors=errors)
    if lowercase:
        text = text.lower()
    if deacc:
        text = deaccent(text)
    return simple_tokenize(text)