File "electrum\gui\qt\network_dialog.py", line 69, in on_update
  File "electrum\gui\qt\network_dialog.py", line 385, in update
  File "electrum\blockchain.py", line 235, in get_name
  File "electrum\blockchain.py", line 487, in get_hash
  File "electrum\blockchain.py", line 186, in func_wrapper
  File "electrum\blockchain.py", line 462, in read_header