Vim supported channels for inter-process communication and job channels communicate with other processes. Also, The vim packages contains the demo channel server(demoserver.py). You can find demoserver.py script in "$VIMRUNTIME/tools/". "$VIMRUNTIME" path, may change according to your distro:
My path, "/usr/share/vim/vim82/tools/demoserver.py" on Gentoo Linux.
First, run the demo server in a terminal.
And then, run Vim in another terminal.
For detailed information, I am quoting from the script:
# Server that will accept connections from a Vim channel. # Run this server and then in Vim you can open the channel: # :let handle = ch_open('localhost:8765') # # Then Vim can send requests to the server: # :let response = ch_sendexpr(handle, 'hello!') # # And you can control Vim by typing a JSON message here, e.g.: # ["ex","echo 'hi there'"] # # There is no prompt, just type a line and press Enter. # To exit cleanly type "quit<Enter>". # # See ":help channel-demo" in Vim. # # This requires Python 2.6 or later.