title: Subclassing of QPushButton
body: <p>I've been looking for a way of subclassing QPushButton, so I can connect 'clicked' signal when constructing new button, like:</p>
  
  <pre><code>Btn = CustomButtonClass('Text', clicked='lambda: self.func(par)')
  </code></pre>
  
  <p>So far - without any success.</p>
  
  <p>I guess the thing is to pass correct parameters to <strong>init</strong>() of CustomButtonClass, but have no idea what, and why.</p>
  
  <p>What I've got:</p>
  
  <pre><code>class CustomButtonClass(QtGui.QPushButton):
      def __init__(self, text, parent=None):
          super().__init__()
  </code></pre>
  
  <p>I also noticed that:</p>
  
  <pre><code>Btn.clicked.connect(lambda: self.func(par))
  </code></pre>
  
  <p>Also doesn't work.</p>
  
  <p>Do I have to override QPushButton's mouseReleaseEvent or construct custom signal to be able to complete my task?</p>