Fastest ever (nothing can be faster)

a = [1, 2, 3, 3, 3, 1, 2, 4, 5, 5, 5, 5]

count = [0] * 10
for e in a:
    count[e] = count[e] + 1

for i, c in enumerate(count):
    if c > 0: print(c, " of ", i)