code: def json_md5(self):
      json_str = json.dumps(vars(self), sort_keys=True)
      return hashlib.md5(json_str.encode("utf-8")).hexdigest()
  
imports: import json
  import hashlib
label_desc: Use image node_id 2 for calling the Env obj's underlying member method code with example usage: obj.json_md5() and returns: hashlib