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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_plot(self, *args, extension='pdf', **kwargs):
 """Save the plot. Returns ------- str The basename with which the plot has been saved. """

        import matplotlib.pyplot as plt

        tmp_path = make_temp_dir()
        filename = '{}.{}'.format(str(uuid.uuid4()), extension.strip('.'))
        filepath = posixpath.join(tmp_path, filename)

        plt.savefig(filepath, *args, **kwargs)
        return filepath