Not able to use global variables in a @app.route block in flask app

Question

from flask import Flask, request, render_template


app = Flask(__name__)

def fun(userAns="True", question="this is first question"):
    if question == "this is first question":
    
        if userAns == "True":
            return "actual first question", "Yes", "No", None
   
    elif question == "actual first question":
        if userAns == "True":
            return "2nd question to be asked after ans = true", "Yes", "No", None
        elif userAns=="False":
            return "2nd question to be asked after ans = false",  "Yes", "No", None

question = None
userAns = None

@app.route("/", methods=["POST", "GET"])
def hello():
    a=0
    while a < 1:
        question = "this is first question"
        userAns = 'True'
        returnValue = fun(userAns, question)
        a += 1
        
    if request.method == "POST":
        userAns = request.form["answer"]
        print(userAns)
        returnValue = fun(userAns, question)
        question=returnValue[0]
    return render_template("index.html",question=returnValue[0], option1= returnValue[1],option2=returnValue[2],option3=returnValue[3])

if __name__ == "__main__":
    app.run(debug=True)

Here I want to call the fun() function in the @app.route , but for that I have to initialize some variables as they will be updated for the next iteration. I observed in the debugger that every variable gets its initial value at the end of @app.route , so I tried to make those variables global, but it didn't take global variables for some reason.

Answer 1

To update a global variable in function use this global variable_name at the start of hello function