flask run application code example

Example 1: export flask app

> set FLASK_APP=hello
> flask run

Example 2: basic flask app python

#Import Flask, if not then install and import.

import os
try:
  from flask import *
except:
  os.system("pip3 install flask")
  from flask import *

app = Flask(__name__)

@app.route("/")
def index():
  return "<h1>Hello World</h1>"

if __name__ == "__main__":
  app.run(host="0.0.0.0", port=8080, debug=False)