code: def count_moves_in_game_range(self, game_begin, game_end):
          
          rows = self.bt_table.read_rows(
              ROWCOUNT_PREFIX.format(game_begin),
              ROWCOUNT_PREFIX.format(game_end),
              filter_=bigtable_row_filters.ColumnRangeFilter(
                  METADATA, MOVE_COUNT, MOVE_COUNT))
          return sum([int(r.cell_value(METADATA, MOVE_COUNT)) for r in rows])
docs: Count the total moves in a game range.
  
          Args:
            game_begin:  integer, starting game
            game_end:  integer, ending game
  
          Uses the `ct_` keyspace for rapid move summary.