how to do email verification python code example

Example: how email verification works python

@user_blueprint.route('/confirm/<token>')
@login_required
def confirm_email(token):
    try:
        email = confirm_token(token)
    except:
        flash('The confirmation link is invalid or has expired.', 'danger')
    user = User.query.filter_by(email=email).first_or_404()
    if user.confirmed:
        flash('Account already confirmed. Please login.', 'success')
    else:
        user.confirmed = True
        user.confirmed_on = datetime.datetime.now()
        db.session.add(user)
        db.session.commit()
        flash('You have confirmed your account. Thanks!', 'success')
    return redirect(url_for('main.home'))