implement flask-healthz for python3

I am trying to implement flask-healthz (https://pypi.org/project/flask-healthz/) for my python application to get return on liveness and rediness probes. But somehow it doesn’t work for me. Below is my code snippet :

from flask import Flask
from flask_healthz import healthz
from flask_healthz import HealthError

def printok():
    print("Everything is fine")

app = Flask(__name__)
app.register_blueprint(healthz, url_prefix="/healthz")

def liveness():
    try:
        printok()
    except Exception:
        raise HealthError("Can't connect to the file")

def readiness():
    try:
        printok()
    except Exception:
        raise HealthError("Can't connect to the file")

HEALTHZ = {
    "live": "yourapp.checks.liveness",
    "ready": "yourapp.checks.readiness",
}

@app.route("/")
def hello():
    return "Hello World!"

if __name__ == "__main__":
    app.run(host='0.0.0.0', port=5000)

And the output to the code is something like below :

(app-root) curl http://localhost:5000/ 
127.0.0.1 - - [02/Jun/2021 01:02:56] "GET / HTTP/1.1" 200 -
Hello World! 



(app-root) curl http://localhost/yourapp/healthz/live
curl: (7) Failed to connect to localhost port 80: Connection refused


(app-root) curl http://localhost:5000/yourapp/healthz/live
127.0.0.1 - - [02/Jun/2021 01:03:23] "GET /yourapp/healthz/live HTTP/1.1" 404 -
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>404 Not Found</title>
<h1>Not Found</h1>
<p>The requested URL was not found on the server. If you entered the URL manually please check your spelling and try again.</p>


(app-root) curl http://localhost:5000/yourapp/healthz/ready
127.0.0.1 - - [02/Jun/2021 01:03:37] "GET /yourapp/healthz/ready HTTP/1.1" 404 -
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>404 Not Found</title>
<h1>Not Found</h1>
<p>The requested URL was not found on the server. If you entered the URL manually please check your spelling and try again.</p>


(app-root) curl http://localhost:5000/healthz/readiness
127.0.0.1 - - [02/Jun/2021 01:04:02] "GET /healthz/readiness HTTP/1.1" 404 -
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>404 Not Found</title>
<h1>Not Found</h1>
<p>The readiness check endpoint is not setup</p>


(app-root) curl http://localhost:5000/healthz/liveness
127.0.0.1 - - [02/Jun/2021 01:04:10] "GET /healthz/liveness HTTP/1.1" 404 -
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>404 Not Found</title>
<h1>Not Found</h1>
<p>The liveness check endpoint is not setup</p>
(app-root) 

Is there something I am doing wrong. I tried to run the same in Openshift well but no luck.

I would appriciate if there is some working example.

Source: Docker Questions

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