title: Why there are pass keywords in functions of Libraries like PyQt5 or Tkinter in Python
body: <p>This is a really unnecessary thing to ask but I am curious about it so I was exploring thorough the scripts of Python Libraries like PyQt5, Tkinter etc. and saw "Pass" keywords in every class functions, why is there no real code and there are only 'pass' keywords.</p>
  
  <p>for example look at this piece of code extracted from PyQt5.QtWidgets.QPushButton:</p>
  
  <pre><code>class QPushButton(QAbstractButton):
      """
      QPushButton(parent: QWidget = None)
      QPushButton(str, parent: QWidget = None)
      QPushButton(QIcon, str, parent: QWidget = None)
      """
      def actionEvent(self, *args, **kwargs): # real signature unknown
          pass
  
      def autoDefault(self): # real signature unknown; restored from __doc__
          """ autoDefault(self) -&gt; bool """
          return False
  
      def changeEvent(self, *args, **kwargs): # real signature unknown
          pass
  
      def checkStateSet(self, *args, **kwargs): # real signature unknown
          pass
  
      def childEvent(self, *args, **kwargs): # real signature unknown
          pass
  
      def closeEvent(self, *args, **kwargs): # real signature unknown
          pass
  
      def connectNotify(self, *args, **kwargs): # real signature unknown
          pass
  
      def contextMenuEvent(self, *args, **kwargs): # real signature unknown
          pass
  
      def create(self, *args, **kwargs): # real signature unknown
          pass
  </code></pre>