title: Python Flask send alert without reloading the whole page
body: <p>I recently started with Flask and web servers and webpages in general. Is there a way to pop up an alert message on the web page through server without reloading the page. The current ways I know of are:</p>
  
  <p>1) Reloading the whole page and calling alert() function in javascript
  2) Using flask's flash() function to send text to place holders in the page.</p>
  
  <p>Both of above require reloading the whole page. I guessing if there is a method we would do something in the return call instead of return render_template(...).</p>
  
  <p>Any help is greatly appreciated. Thank you.</p>
  
  <p>Edit [Not Duplicate]: This question is not asking how to use AJAX with Flask. At the time of the question I wasn't aware of using flask to do this.</p>