'Display an error message within the Login page when the password is wrong

I'm making a form within a website to register and then log in. Both registration and login work without problems, but within the job I must do is that, when I enter the password incorrectly in the Login, it sends me an error message that the password is incorrect. I've found some ways to do it, but when I try it, the page goes blank with the text "none" Here's the code:

import sqlite3 as sql
import web

web.config.debug = False

urls = (
    '/login', 'Login',
    '/signup', 'Signup',
    '/inicio', 'Inicio',
)

app =  web.application(urls, globals())
render = web.template.render('views')


class Login:
    def GET(self):
        return render.login() 
            
    def POST(self):
        import sys
        try:
            formulario = web.input()
            email = formulario.email
            password = formulario.password
            conn =  sql.connect('test.db')
            cur = conn.cursor()
            statement = f"SELECT * from USUARIOS WHERE EMAIL='{email}' AND PASSWORD='{password}'" #crea una variable donde se almacenara la consulta a la base de datos con los datos que ingresamos en el formulario
            cur.execute(statement) #ejecuta la consulta
            if cur.fetchone():#se comprueba el retorno de datos
                return web.seeother("inicio")#redirecciona a otra pagina web
        except Exception:
            print(sys.stderr, "Login Failed")
            return render.login("usuario incorrecto")



class Signup:
    def GET(self):
        return render.signup() 
            
    def POST(self):
        try:
            formulario = web.input()
            email = formulario.email
            password = formulario.password
            print("el correo es ", email, " y la contraseña es ", password)
            conn =  sql.connect('test.db')
            cur = conn.cursor()
            insertStat = f"INSERT INTO USUARIOS(EMAIL, PASSWORD) VALUES ('{email}', '{password}')"#crea una variable donde se almacenara la operacion de insertar a la base de datos con los datos que ingresamos en el formulario
            cur.execute(insertStat)
            conn.commit()#guardamos los dato que hemos ingresado
            statement = f"SELECT * from USUARIOS WHERE EMAIL='{email}' AND PASSWORD='{password}'"#crea una variable donde se almacenara la consulta a la base de datos con los datos que ingresamos en el formulario
            cur.execute(statement) #ejecuta la consulta
            if cur.fetchone():#se comprueba el retorno de datos
                return web.seeother("login")#redirecciona a otra pagina web
        except Exception:
            


class Inicio:
    def GET(self):
        return render.inicio() # renderiza a inicio.html
        



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

It is supposed that in the Except should place for error, but the forms that I tried or did not usually work or send me to the same screen with the NONE.

Html:

$def with (message)
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Login</title>
</head>
<body>
    <p>$message</p>
    <h1>Login</h1>
    <form action="" method="POST">
        <label for="">CORREO</label>
        <input type="email" name="email" id="email">
        <label for="">CONTRASEÑA</label>
        <input type="password" name="password" id="password">
        <input type="submit" value="Login">
    </form>
</body>
</html>

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'Display an error message within the Login page when the password is wrong

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