File "site-packages\electrum-3.1.0-py3.5.egg\electrum_gui\qt\main_window.py", line 480, in <lambda>
  File "site-packages\electrum-3.1.0-py3.5.egg\electrum_gui\qt\util.py", line 556, in toggle_toolbar
  File "site-packages\electrum-3.1.0-py3.5.egg\electrum_gui\qt\util.py", line 549, in show_toolbar
  File "site-packages\electrum-3.1.0-py3.5.egg\electrum_gui\qt\address_list.py", line 63, in save_toolbar_state
  File "site-packages\electrum-3.1.0-py3.5.egg\electrum\simple_config.py", line 140, in set_key
  File "site-packages\electrum-3.1.0-py3.5.egg\electrum\simple_config.py", line 149, in _set_key_in_user_config
  File "site-packages\electrum-3.1.0-py3.5.egg\electrum\simple_config.py", line 215, in save_user_config