class_docstr: A SessionStorage that stores sessions in memory.
  
  At most maxsize sessions are stored with a TTL of ttl seconds. This class is really
  just a thin wrapper around cachetools.TTLCache that complies with the SessionStorage
  protocol.
code: def list(self) -> List[SessionInfo]:
      return list(self._cache.values())
  
file_path: streamlit/lib/streamlit/runtime/memory_session_storage.py
imports: from typing import List, MutableMapping, Optional
  from cachetools import TTLCache
  from streamlit.runtime.session_manager import SessionInfo, SessionStorage
label_desc: Use image node_id 5 for calling the MemorySessionStorage obj's underlying member method code with example usage: obj.list() and returns: list