code: def _restore_env_var(self, key):
      if value := self.env.get(key):
          os.environ[key] = value
      else:
          del os.environ[key]
  
file_path: mlflow/examples/auth/auth.py
imports: import os
  import uuid
  import mlflow.server
label_desc: Use image node_id 3 for calling the User obj's underlying member method code with example usage: obj._restore_env_var(key) without return types