code: def tobytes(o):
      if isinstance(o, str):
          return o.encode("utf8")
      return o
  
imports: import contextlib
  import io
  import random
  import socket
  import subprocess
  import sys
  import threading
  import uuid
  import numpy
label_desc: Use image node_id 4 for calling a global function with example usage: tobytes(o) and returns: o, o