code: def flatten_all(self):
          
  
          log.info("flattening - START")
  
          self.all_rows = []
  
          for idx, r in enumerate(self.all_flat):
  
              new_row = {"idx": idx}
  
              for k in self.all_keys_list:
                  if k in r:
                      new_row[k] = r[k]
                  else:
                      new_row[k] = None
              # end of for all keys
  
              self.all_rows.append(new_row)
  
          # end of all_keys
  
          log.info("flattening - END")
docs: flatten_all