title: how to create click of button in PYQT
body: <p>I've been having some trouble with create click of buttons in PyQT.
  when i create click of button as below , this picture can't save </p>
  
  <pre><code>        cv.SetImageROI(image, (pt1[0],pt1[1],pt2[0] - pt1[0],int((pt2[1] - pt1[1]) * 1)))
          if self.Button.click():
              cv.SaveImage('example.jpg', image)
  
      cv.ResetImageROI(image)
  </code></pre>