Create a report using excel

[mamta_parida]

The code is mentioned below

    def out(self):
        global part,part2,part3,part4,TEST_PASS,TEST_FAIL,output1,output2,output3,output4,serial_no1,serial_no2,serial_no3,serial_no4
        output1 = self.clicked1()
        output2 = self.clicked2()
        output3 = self.clicked3()
        output4 = self.clicked4()
        showtime = strftime("%Y-%m-%d %H:%M:%S")
        serial_no1 = part.get()
        serial_no2 = part2.get()
        serial_no3 = part3.get()
        serial_no4 = part4.get()
        todays_date = str(datetime.datetime.now().strftime("%Y%m%d%H%M"))
        workbook = xlsxwriter.Workbook('Automation_Test_Report'+ todays_date + '.xlsx')
        worksheet = workbook.add_worksheet()
        bold = workbook.add_format({'bold': True})

        cell_format1 = workbook.add_format()
        cell_format1.set_pattern(1)  # This is optional when using a solid fill.
        cell_format1.set_bg_color('#00FF00')

        cell_format2 = workbook.add_format()
        cell_format2.set_pattern(1)  # This is optional when using a solid fill.
        cell_format2.set_bg_color('#FF0000')

        cell_format3 = workbook.add_format()
        cell_format3.set_pattern(1)  # This is optional when using a solid fill.
        cell_format3.set_bg_color('#FFFF00')

        cell_format4 = workbook.add_format()
        cell_format4.set_align('center')

        header_format = workbook.add_format({
            'bold': True,
            'text_wrap': True,
            'align': 'Center',
            'fg_color': '#D7E4BC',
            'border': 1})

        merge_format = workbook.add_format({
            'bold': 1,
            'border': 1,
            'align': 'center',
            'valign': 'vcenter',
            'fg_color': '#D7E4BC'})

        merge_format1 = workbook.add_format({
            'bold': 1,
            'border': 1,
            'align': 'center',
            'valign': 'vcenter',
            'fg_color': '#FF6600'})

        worksheet.set_column('A:B', 15)
        worksheet.set_column('C:D', 15)
        worksheet.set_column('E:F', 15)
        worksheet.set_column('G:H', 15)
        worksheet.set_column('I:J', 15)
        worksheet.set_column('K:L', 15)
        worksheet.set_column('M:N', 15)
        worksheet.merge_range('B1:N1', 'AUTOMATION TESTING - ITOM', merge_format1)
        worksheet.write('B3', 'DATE & TIME', bold)
        worksheet.write('C3', showtime)
        worksheet.write('B5', 'SERIAL NO', header_format)
        worksheet.merge_range('C5:D5', 'TEST CASE-1', merge_format)
        worksheet.merge_range('E5:F5', 'TEST CASE-2', merge_format)
        worksheet.merge_range('G5:H5', 'TEST CASE-3', merge_format)
        worksheet.merge_range('I5:J5', 'TEST CASE-4', merge_format)
        worksheet.merge_range('K5:L5', 'TEST CASE-5', merge_format)
        worksheet.merge_range('M5:N5', 'TEST CASE-6', merge_format)
        worksheet.write('B6', '', header_format)
        worksheet.write('C6', 'Value', header_format)
        worksheet.write('D6', 'Relay', header_format)
        worksheet.write('E6', 'Value', header_format)
        worksheet.write('F6', 'Analogue Output', header_format)
        worksheet.write('G6', 'Value', header_format)
        worksheet.write('H6', 'LED Testing', header_format)
        worksheet.write('I6', 'Value', header_format)
        worksheet.write('J6', 'Bluetooth',header_format)
        worksheet.write('K6', 'Value', header_format)
        worksheet.write('L6', 'Room Temperature', header_format)
        worksheet.write('M6', 'Value', header_format)
        worksheet.write('N6', 'Humidity', header_format)
        
        output_result=(
            [serial_no1,ch_data1,output1],
            [serial_no2,ch_data2,output2],
            [serial_no3,ch_data3,output3],
            [serial_no4,ch_data4,output4]
        )

        row = 7
        column = 1
        i = 0
        j = 0

        for i in range(4):
            for j in range(3):
                worksheet.write(row, column, output_result[i][j])
                #worksheet.write(row, col+1, Value)
                #worksheet.write(row, col+2, Relay)
                j=j+1
                column = column + 1
            row = row + 1
            column = 1
            j = 0
            i = i +1
        workbook.close()

This is my code where i'm creating a file using xlsxwriter. My worries is how to append the data in next row in same above file. One more thing due to date and time always it create multiple file for me.
Can you plz suggest how to create an excel file and append data in same file one by one