@celery.task
def send_async_email(data, email):
    """Background task to send an email with Flask-Mail."""
    with app.app_context():
        find_book = FindBook(data)
        # штука которая долго делается
        result = find_book.search_books()
        msg = Message("You've requested search for %s" % data,
                      recipients=[email])
        msg.body = 'This is a test email sent from a background Celery task.'
        msg.html = render_template('mail.html', result=result)
        mail.send(msg)
 
 
 
 
def search():
    form = SearchForm()
    if form.validate_on_submit():
        send_async_email.delay(form.search.data, form.email.data)
        return redirect(url_for('success'))
 
    return render_template('search.html', title='Search', form=form)

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