line_prime.py

import sys


def main():
    n = int(sys.argv[1])
    print(nth_prime(n))


def nth_prime(n):

    primes = [2]
    k = 3

    while len(primes) < n:

        is_prime = True

        for p in primes:
            if p * p > k:
                break
            if k % p == 0:
                is_prime = False
                break

        if is_prime:
            primes.append(k)

        k += 2

    return primes[-1]


if __name__ == "__main__":
    main()