shoe_sizes = [7, 8, 8, 9, 9, 9, 10, 11]

counts = {}
for size in shoe_sizes:
    counts[size] = counts.get(size, 0) + 1

print(counts)
# {7: 1, 8: 2, 9: 3, 10: 1, 11: 1}

mode = max(counts, key=counts.get)
print("Mode:", mode)
# Mode: 9