from openpyxl import Workbook

def main(txtFileName):
    new_XlsxFileName = txtFileName[:-3] + 'xlsx'
    wb = Workbook()
    ws = wb.worksheets[0]
    with open(txtFileName) as fp:
        for line in fp:
            line = line.strip().split(',')
            ws.append(line)
    wb.save(new_XlsxFileName)

main('test.txt')