title: How to connect between HTML button and python(or flask) function?
body: <p>In flask programming, people usually use '<code>url_for</code>' such as <code>{{url_for = 'some url'}}</code>
  This way have to make URL(<code>@app.route</code>), template(HTML) and map each other.</p>
  
  <p>But, I just want to send email when I click submit button in HTML modal.
  For this, There is no page reloading. To do this, I think I have to connect between button and python function without URL, return(response)</p>
  
  <p>I wonder that how to make it, help me please, I'm beginner in flask programming.</p>