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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 tone_marks(text):
 """Add a space after tone-modifying punctuation. Because the `tone_marks` tokenizer case will split after a tone-modidfying punctuation mark, make sure there's whitespace after. """

    return PreProcessorRegex(
        search_args=symbols.TONE_MARKS,
        search_func=lambda x: u"(?<={})".format(x),
        repl=' ').run(text)