code: def readable_bytes_string(bytes):
      """Get a human-readable string for number of bytes."""
      if bytes >= 2**20:
          return "%.1f MB" % (float(bytes) / 2**20)
      elif bytes >= 2**10:
          return "%.1f kB" % (float(bytes) / 2**10)
      else:
          return "%d B" % bytes
  
imports: import contextlib
  from datetime import datetime
  import sys
  import time
label_desc: Use image node_id 2 for calling a global function with example usage: readable_bytes_string(bytes) and returns: unknown, unknown, unknown