code: def save_sparse_data(self, fname):
          
          data = self.adata_raw.X.T
          if data.getformat()=='csr':
              data=data.tocsc()
  
          cell_names = np.array(list(self.adata_raw.obs_names))
          gene_names = np.array(list(self.adata_raw.var_names))
          
          pickle.dump((data, cell_names, gene_names), open(fname, 'wb'))
docs: Saves the tuple (raw_data,all_cell_names,all_gene_names) in a
          Pickle file.
  
          Parameters
          ----------
          fname - string
              The filename of the output file.