File "/usr/local/lib/python3.5/dist-packages/electrum/util.py", line 882, in run_with_except_hook
    run_original(*args2, **kwargs2)
  File "/usr/local/lib/python3.5/dist-packages/electrum/network.py", line 1085, in run
    self.wait_on_sockets()
  File "/usr/local/lib/python3.5/dist-packages/electrum/network.py", line 1067, in wait_on_sockets
    self.process_responses(interface)
  File "/usr/local/lib/python3.5/dist-packages/electrum/network.py", line 719, in process_responses
    self.process_response(interface, response, callbacks)
  File "/usr/local/lib/python3.5/dist-packages/electrum/network.py", line 624, in process_response
    self.on_notify_header(interface, result)
  File "/usr/local/lib/python3.5/dist-packages/electrum/network.py", line 1122, in on_notify_header
    b.save_header(header)
  File "/usr/local/lib/python3.5/dist-packages/electrum/blockchain.py", line 126, in func_wrapper
    return func(self, *args, **kwargs)
  File "/usr/local/lib/python3.5/dist-packages/electrum/blockchain.py", line 282, in save_header
    self.write(data, delta*80)
  File "/usr/local/lib/python3.5/dist-packages/electrum/blockchain.py", line 272, in write
    os.fsync(f.fileno())