How to fix WinError 10049 when changing host on Flask server?

Question

Flask

Hello. I wanted to check if the page will be opened from another computer on the Internet if I pass it as an argument when starting the server in flask: app.run(debug=True, host='ip'), where ip is my ip on the Internet (looked at https:// myip.ru/ , I'm sitting at the router). When running the script, it gives an error: OSError: [WinError 10049] The required address for its context is incorrect. Why? Miguel Greenberg's Flask book doesn't mention this. It only says: "... the web server will be accessible from any computer on the network at: ' abcd:5000 ', where "abcd" is the external IP address of the computer where the web server is running."

Answer 1

I'm sitting at the router

It is necessary to open a port on the router and forward it to the local machine with a flask.
app.run(debug=True, host='your local ip address behind the router, like 192.168...')