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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 is_training_modified(self):
 """ Returns `True` if training data was modified since last training. Returns `False` otherwise, or if using builtin training data. """


        last_modified = self.trainer.get_last_modified()
        if last_modified > self.training_timestamp:
            return True
        else:
            return False