def get_last(row, column, default=nil)
      r = get(row, column)
      (r.length > 0) ? r.first.value : default
    end
def get_last(row, column, default=nil)
      r = get(row, column)
      (r.length > 0) ? r.first.value : default
    end
get the last value for the given row / column