def login_user():
    if request.method == "POST":
        # Check login is valid
        email = request.form["email"]
        password = request.form["password"]

        try:
            if User.check_login_valid(email, password):
                session["email"] = email
                return redirect(url_for(".user_alerts"))

        except UserErrors.UserError as e:
            return e.message

    return render_template(
        "users/login.jinja2"
    )  # Send the user an error if their login is invalid