webserver - Trying to make a simple python web server and its not starting

Question

Ive been trying to make a web server and I have the code down that should be able to get it running but when I go in to the Command Prompt and type python app.py it doesn't run when it should this is the code that I have

from flask import Flask
app = Flask(__name__)

@app.route("/")
def main():
    return "Welcome to my Flask page"

if __name__ == "__main__":
    app.run(debug = True, host = "0.0.0.0", port=80)```

Answer 1

I think the problem is port 80. Which OS are you using? Ports under 1024 need root privileges, there is also a possibility that it is not working because some other service (like Apache) is running on this port.

So either fixing privileges or services or changing the port should make it run.