nums = [10, 5, 20, 8]

diff = max(nums) - min(nums)
print("Difference:", diff)

Difference: 15

num = int(input("Enter number: "))

if int(num ** 0.5) ** 2 == num:
    print("Perfect square")
else:
    print("Not perfect square")

Enter number:  6


Not perfect square

nums = ['a', 'b', 'c']
result = "".join(nums)

print(result)

abc