class_docstr: RL learning environment.
  
  This serves a minimal interface for RL agents.
class_docstr_tok: ["RL","learning","environment",".","This","serves","a","minimal","interface","for","RL","agents","."]
code: def close(self):
      raise NotImplementedError()
  
file_path: chainerrl/chainerrl/env.py
imports: from abc import ABCMeta
  from abc import abstractmethod
label_desc: Use image node_id 3 for calling the Env obj's underlying member method code with example usage: obj.close() without return types