title: How to combine columns in a layout (colspan feature)
body: <p>I have this code:</p>
  
  <pre><code>#!/usr/bin/env python3
  
  from PyQt5.QtWidgets import *
  import sys    
  
  class Window(QWidget):
      def __init__(self):
          QWidget.__init__(self)
  
          layout = QGridLayout()
          self.setLayout(layout)
  
          label_1 = QLabel("label 1")
          layout.addWidget(label_1, 0, 0)
  
          label_2 = QLabel("label 2")
          layout.addWidget(label_2, 0, 1)
  
          label_3 = QLabel("label 3")
          layout.addWidget(label_3, 1, 0)
  
  
  app = QApplication(sys.argv)
  
  screen = Window()
  screen.show()
  
  sys.exit(app.exec_())
  </code></pre>
  
  <p>I have this result:</p>
  
  <p><img src="https://i.stack.imgur.com/4Hv7L.png" alt="image example of current code"></p>
  
  <p>but I need this:</p>
  
  <p><img src="https://i.stack.imgur.com/ApOhK.png" alt="image example of code which I need"></p>
  
  <p>How can I do it?</p>