import random
import time
from sympy import isprime, mod_inverse

def get_prime(bits):
    while True:
        p = 2 * random.getrandbits(bits-1) + 1
        if isprime(p):
            return p

def gen_rsa(bits):
    p = get_prime(bits)
    q = get_prime(bits)
    n = p * q
    phi = (p - 1) * (q - 1)
    e = 65537
    while phi % e == 0:
        e = random.randrange(3, phi, 2)
    d = mod_inverse(e, phi)
    return (e, n), (d, n)

##########################################################
random.seed(int(time.time()))
pk, sk = gen_rsa(2000)