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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=""):
 """ Tokenize text into words. @param text: the input text. @type text: unicode. @return: list of words. @rtype: list. """

    if text == '':
        return []
    else:
        # split tokens
        mylist = TOKEN_PATTERN.split(text)
        # don't remove newline \n
        mylist = [TOKEN_REPLACE.sub('', x) for x in mylist if x]
        # remove empty substring
        mylist = [x for x in mylist if x]
        return mylist