code: def _set_up_savefolder(self):
          
          if not os.path.isdir(self.cells_path):
              os.mkdir(self.cells_path)
  
          if not os.path.isdir(self.figures_path):
              os.mkdir(self.figures_path)
  
          if not os.path.isdir(self.populations_path):
              os.mkdir(self.populations_path)
docs: Create catalogs for different file output to clean up savefolder.