Lottery Simulator - it`s hard to win the lottery

Lottery Distribution

import random

# example data

#generate random set
x = []
i = 1
while i < 10000000:
    l = random.sample(range(1, 60), 6)
    str1 = '-'.join(str(e) for e in l)
    x.append(str1)
    i += 1

#print x

#calculate frequency distribution

unique_values = set(x)
freq_distribution = {}

for i in unique_values:
    freq_distribution[i] = 0

for i in x:
    freq_distribution[i] += 1

#get distributions with frequency higher than 1
counter = 0

print "---------------------------"
print "Random Set - Frequency"
print "---------------------------"
for k, v in freq_distribution.iteritems():  # note use of iteritems()
    if v > 1:
        print " {0} - {1}".format(k, v)
        counter += 1
print "total:", counter
print "-----"