code: def _machine_bytes():
      
      machine_hash = hashlib.md5()
      if PY3:
          # gethostname() returns a unicode string in python 3.x
          # while update() requires a byte string.
          machine_hash.update(socket.gethostname().encode())
      else:
          # Calling encode() here will fail with non-ascii hostnames
          machine_hash.update(socket.gethostname())
      return machine_hash.digest()[0:3]
docs: Get the machine portion of an ObjectId.