def sieve(n: int) -> list:
"""
Sieve away and only primes are left.
"""
primes = 2*[False] + (n-1)*[True]
for i in range(2, int(n**0.5+1.5)):
for j in range(i*i, n+1, i):
primes[j] = False
return [prime for prime, checked in enumerate(primes) if checked]
if __name__ == '__main__':
print(sieve(100))
