n = 20
primes = []
for i in range(2, n + 1):
for j in range(2, int(i ** 0.5) + 1):
if i%j == 0:
break
else:
primes.append(i)
print(primes)
print([i for i in range(2, int(input("Enter your number: "))+1) if 0 not in [i%n for n in range(2, i)]])
>>> [x for x in range(2, 20)
if all(x % y != 0 for y in range(2, x))]
[2, 3, 5, 7, 11, 13, 17, 19]