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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 tokenstream(self, data_dict):
 """Yields a list of tokens resulting from expansion. This may be useful for WSGI apps. NOTE: In the current implementation, the entire expanded template must be stored memory. NOTE: This is a generator, but JavaScript doesn't have generators. """

        tokens = []
        self.execute(data_dict, tokens.append)
        for token in tokens:
            yield token