def merge_range_with_date_time(*args)
    # Check for a cell reference in A1 notation and substitute row and column
    args = row_col_notation(args)

    raise "Incorrect number of arguments" if args.size != 6 and args.size != 7
    raise "Format argument is not a format object" unless args[5].respond_to?(:xf_index)

    rwFirst  = args[0]
    colFirst = args[1]
    rwLast   = args[2]
    colLast  = args[3]
    string   = args[4]
    format   = args[5]
    encoding = nil

    merge_range_core(rwFirst, colFirst, rwLast, colLast, string, format, encoding) do |rwFirst, colFirst, string, format, encoding|
      write_date_time(rwFirst, colFirst, string, format)
    end
  end
def merge_range_with_date_time(*args)
    # Check for a cell reference in A1 notation and substitute row and column
    args = row_col_notation(args)

    raise "Incorrect number of arguments" if args.size != 6 and args.size != 7
    raise "Format argument is not a format object" unless args[5].respond_to?(:xf_index)

    rwFirst  = args[0]
    colFirst = args[1]
    rwLast   = args[2]
    colLast  = args[3]
    string   = args[4]
    format   = args[5]
    encoding = nil

    merge_range_core(rwFirst, colFirst, rwLast, colLast, string, format, encoding) do |rwFirst, colFirst, string, format, encoding|
      write_date_time(rwFirst, colFirst, string, format)
    end
  end
:call-seq:
   merge_range_with_date_time(first_row, first_col, last_row, last_col, token, format)

 Write to meged cells, a datetime string in ISO8601 "yyyy-mm-ddThh:mm:ss.ss" format as a
 number representing an Excel date. format is optional.