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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 save(self, filepath):
 """ Saves the classifier to `filepath`. Because this classifier needs to save the dataset, it must be something that can be pickled and not something like an iterator. """


        if not filepath or not isinstance(filepath, str):
            raise ValueError("Invalid filepath")

        with open(filepath, "wb") as filehandler:
            pickle.dump(self, filehandler)