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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, foldername: str, path_to_folder: str=None) -> None:
        ''' Saves entities into multiple files within the same folder because of pickle-recursive
            errors that would happen if squeezed into one '''
        self.create_pickle((self.g.namespaces, ))
        self.df.to_pickle(output)