OutputReply.output_reply is "None" (str) instead of None like it was with i3ipc 1.7.1.
>>> import i3ipc
>>> i3 = i3ipc.Connection()
>>> outputs = i3.get_outputs()
>>> [o.current_workspace for o in outputs]
['NET', 'None', 'TERM']
Also the documentations states that it should be null in that case, it is ambigus if it should be None or the string "null" :
current_workspace (str) – The name of the current workspace that is visible on this output. null if the output is not active.
https://i3ipc-python.readthedocs.io/en/latest/replies.html#i3ipc.OutputReply
Environment :