code: def _get_full_key(self, key):
          
  
          length = len(key)
  
          if length == 3:
              return key
  
          elif length == 2:
              row, col = key
              tab = self.grid.current_table
              return row, col, tab
  
          else:
              msg = _("Key length {length}  not in (2, 3)").format(length=length)
              raise ValueError(msg)
docs: Returns full key even if table is omitted