exporting data into a column of an excel file in python

here is my code:

import random
from random import shuffle

fileName = 'test'
dataFile = open("DD" + fileName+'.csv', 'w')
dataFile.write('trial,numbers') #data headers for .csv file

a = [1,2]

for i in range(4):
     shuffle(a)
     if a == [1,2]:
         num = 'top'
     else:
         num = 'bottom'

    print a
    print num

    info = []
    i = str(i)
    info.append(',')
    info.append(i)
    info.append(',')
    info.append(num)

    dataFile.writelines(info)

This code randomizes an order than labels it top or bottom 4 times, and exports the a excel file. The problem is that when it exports it puts it in a row. What I would like to do is have it exported into a column so that they are under the headlines 'trial' and 'numbers'. Any help would be greatly appreciated. :)