File "electrum\gui\qt\main_window.py", line 1171, in <lambda>
  File "electrum\gui\qt\main_window.py", line 1275, in create_invoice
  File "electrum\lnworker.py", line 1145, in add_request
  File "concurrent\futures\_base.py", line 435, in result
  File "concurrent\futures\_base.py", line 384, in __get_result
  File "electrum\lnworker.py", line 1177, in _add_request_coro
  File "electrum\util.py", line 1039, in wrapper
  File "electrum\lnworker.py", line 1172, in create_invoice
  File "electrum\lnworker.py", line 1187, in save_preimage
  File "electrum\wallet.py", line 293, in save_db
  File "electrum\wallet_db.py", line 1224, in write
  File "electrum\wallet_db.py", line 1232, in _write
  File "electrum\util.py", line 406, in <lambda>
  File "electrum\util.py", line 402, in do_profile
  File "electrum\storage.py", line 98, in write