docs: def make_rsa_keys(bits=2048, e=65537, k=64):
      """
      Create RSA key pair.
  
      Returns n, e, d, where (n, e) is the public
      key and (n, e, d) is the private key (and k is
      the number of rounds used in the Miller-Rabin
      primality test).
  
      """
      p, q = None, None
      while p == q:
          p, q = get_prime(bits // 2), get_prime(bits // 2)
      n = p * q
      phi_n = phi(n, p, q)
      d = mult_inv(e, phi_n)
      return n, e, d