Traceback (most recent call last):
  File "electrum/gui/qt/main_window.py", line 2508, in closeEvent
  File "electrum/gui/qt/main_window.py", line 2539, in clean_up
  File "electrum/gui/qt/__init__.py", line 485, in close_window
  File "electrum/daemon.py", line 552, in stop_wallet
  File "concurrent/futures/_base.py", line 458, in result
  File "concurrent/futures/_base.py", line 403, in __get_result
  File "electrum/daemon.py", line 561, in _stop_wallet
  File "electrum/wallet.py", line 544, in stop
  File "electrum/wallet.py", line 479, in save_db
  File "electrum/json_db.py", line 48, in wrapper
  File "electrum/json_db.py", line 398, in write
  File "electrum/json_db.py", line 48, in wrapper
  File "electrum/json_db.py", line 409, in _append_pending_changes
  File "electrum/storage.py", line 112, in append
FileNotFoundError: [Errno 2] No such file or directory: '/Users/zhanglongfei/.electrum/wallets/wallet_1'