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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_words(string):
 """ Tokenize input text to words. :param string: Text to tokenize :type string: str or unicode :return: words :rtype: list of strings """

    string = six.text_type(string)
    return re.findall(WORD_TOKENIZATION_RULES, string)