without the host as a parameter of app.run() function, the default host will be the 127.0.0.1 which is a loopback address only for local machine. External user will be unable to connect to the server.
I believe all of our servers are just running on 127.0.0.1 which is our expectation. Sharing a link with external users is outside the scope of this tutorial at this point.
without the host as a parameter of app.run() function, the default host will be the 127.0.0.1 which is a loopback address only for local machine. External user will be unable to connect to the server.