code: def default(val, d):
      if exists(val):
          return val
      return d() if isfunction(d) else d
  
file_path: ColossalAI/examples/images/diffusion/ldm/util.py
imports: import importlib
  from inspect import isfunction
  import numpy
  import torch
  from PIL import Image, ImageDraw, ImageFont
  from torch import optim
label_desc: Use image node_id 5 for calling a global function with example usage: default(val, d) and returns: unknown, val