python - gaierror: [Errno 8] nodename nor servname provided, or not known (with macOS Sierra)

Question

socket.gethostbyname(socket.gethostname()) worked well on OS X El Capitan. However, it's not working now after the Mac updated to macOS Sierra.

Thanks!

import socket
socket.gethostbyname(socket.gethostname())

Traceback (most recent call last):
  File "<pyshell#26>", line 1, in <module>
    socket.gethostbyname(socket.gethostname())
gaierror: [Errno 8] nodename nor servname provided, or not known

Answer 1

There is an answer in OP's comments based on another question, which requires to edit /etc/hosts, i.e echo 127.0.0.1 $HOSTNAME >> /etc/hosts.

Alternatively, you can use socket.gethostbyname('localhost'), assuming that localhost is what you need and it is defined in your /etc/hosts.