File "electrum\gui\qt\network_dialog.py", line 77, in on_update
  File "electrum\gui\qt\network_dialog.py", line 366, in update
  File "electrum\gui\qt\network_dialog.py", line 153, in update
  File "electrum\blockchain.py", line 250, in get_name
  File "electrum\blockchain.py", line 517, in get_hash
  File "electrum\blockchain.py", line 201, in func_wrapper
  File "electrum\blockchain.py", line 478, in read_header