title: Update and render a value from Flask periodically
body: <p>I want to display my CPU usage dynamically.  I don't want to reload the page to see a new value.  I know how to get the CPU usage in Python.  Right now I render a template with the value.  How can I continually update a page with a value from Flask?</p>
  
  <pre><code>@app.route('/show_cpu')
  def show_cpu():
      cpu = getCpuLoad()
      return render_template('show_cpu.html', cpu=cpu)
  </code></pre>