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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 get_tokens(self, format_string):
 """ Tokenize a logging format string. :param format_string: The logging format string. :returns: A list of strings with formatting directives separated from surrounding text. """

        return [t for t in self.tokenize_pattern.split(format_string) if t]