title: Flask Blueprint Putting something on session
body: <p>I was trying to put </p>
  
  <pre><code>session['logged_in'] = True
  </code></pre>
  
  <p>in the session, but in another blueprint it doesn't persist... Why is that?</p>
  
  <p>Is there any better way to keep something in the session?</p>
  
  <p>Extended:</p>
  
  <p>I have a blueprint giving a form to login. When done and submitted, it will set a session key like above. Then it redirects via </p>
  
  <blockquote>
    <p>return redirect(url_for('admin.index'))</p>
  </blockquote>
  
  <p>to admin page where If I call the key via </p>
  
  <blockquote>
    <p>session.get('logged_in')</p>
  </blockquote>
  
  <p>I get "None" Instead of the True or False one.</p>