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