Why two unique child process not generating unique random number?

```
import os
import string
import random

def id_generator(size=6, chars=string.ascii_uppercase + string.digits):
  print ''.join(random.choice(chars) for x in range(size)).lower()
  os._exit(0)

for i in range(2):
  newpid = os.fork()
  if newpid == 0:
     id_generator()
  else:
    print "Parent"

```

Output is showing same random number:

```
Parent
Parent
q52mno
q52mno

```