old_contents: 
  
  
  def run(args=None):
      """Main entry point of the application."""
      pass
  
new_contents: import sys
  
  from PyQt4.QtGui import QApplication, QMainWindow
  
  from kodos.ui.ui_main import Ui_MainWindow
  
  
  class KodosMainWindow(QMainWindow, Ui_MainWindow):
      def __init__(self, parent=None):
          super(KodosMainWindow, self).__init__(parent)
          self.setupUi(self)
          self.connectActions()
  
          # Trigger the textChanged signal
          for widget in [self.regexText, self.searchText, self.replaceText]:
              widget.setPlainText('')
  
      def connectActions(self):
          # Connect input widgets to update the GUI when their text change
          for widget in [self.regexText, self.searchText, self.replaceText]:
              widget.textChanged.connect(self.on_compute_regex)
  
      def on_compute_regex(self):
          regex = self.regexText.toPlainText()
          search = self.searchText.toPlainText()
          replace = self.replaceText.toPlainText()
  
          if regex == "" or search == "":
              self.statusbar.showMessage(
                  "Please enter a regex and a search to work on")
          else:
              self.statusbar.clearMessage()
  
  
  def run(args=None):
      """Main entry point of the application."""
  
      app = QApplication(sys.argv)
      kodos = KodosMainWindow()
      kodos.show()
      app.exec_()
  
subject: Connect the UI to the code and start to connect slots to actions.