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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, format=None):
 """ tokenize text for word segmentation :param text: raw text input :return: tokenize text """

    text = Text(text)
    text = text.replace("\t", " ")
    tokens = re.findall(patterns, text)
    tokens = [token[0] for token in tokens]
    if format == "text":
        return " ".join(tokens)
    else:
        return tokens