'Test write_datetime with default date format.'

def test_create_file_default_date_format(self):

    workbook = Workbook(self.got_filename, {'default_date_format': 'yyyy\\-mm\\-dd'})
    worksheet = workbook.add_worksheet()
    worksheet.set_column(0, 0, 12)
    date1 = datetime.strptime('2013-07-25', '%Y-%m-%d')
    worksheet.write_datetime(0, 0, date1)
    workbook.close()
    self.assertExcelEqual()
