ex-machina.py

# BlueBook code decryption
import sys
def sieve(n):
# Compute primes using sieve of Eratosthenes
  x = [1] * n
  x[1] = 0
  for i in range(2,n//2):
    j = 2 * i
    while j < n:
      x[j] = 0
      j = j+i
  return x
def prime(n, x):
# Find nth prime
  i = 1
  j = 1
  while j <= n:
    if x[i] == 1:
      j = j + 1
    i = i + 1
  return i - 1
# Compute BlueBook unlock code
x = sieve(10000)
code = [1206, 301, 384, 5]
key =[1, 1, 2, 2]
sys.stdout.write(''.join(chr(i) for i in [73,83,66,78,32,61,32]))
for i in range(0, 4):
  sys.stdout.write(str(prime(code[i],x)-key[i]))

Very cool!