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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 simple_preprocess(doc, deacc=False, min_len=2, max_len=15):
 """ Convert a document into a list of tokens. This lowercases, tokenizes, de-accents (optional). -- the output are final tokens = unicode strings, that won't be processed any further. """

    tokens = [
        token for token in tokenize(doc, lower=True, deacc=deacc, errors='ignore')
        if min_len <= len(token) <= max_len and not token.startswith('_')
    ]
    return tokens