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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 find_tokens(self, string, **kwargs):
 """ Returns a list of sentences from the given string. Punctuation marks are separated from each word by a space. """

        # "The cat purs." => ["The cat purs ."]
        return find_tokens(string,
                punctuation = kwargs.get(  "punctuation", PUNCTUATION),
              abbreviations = kwargs.get("abbreviations", ABBREVIATIONS),
                    replace = kwargs.get(      "replace", replacements),
                  linebreak = r"\n{2,}")