code: def keyPressEvent(self, event):
          
          if event.key() == Qt.Key_Return or event.key() == Qt.Key_Enter:
              if self.add_current_text_if_valid():
                  self.selected()
                  self.hide_completer()
          elif event.key() == Qt.Key_Escape:
              self.set_current_text(self.selected_text)
              self.hide_completer()
          else:
              QComboBox.keyPressEvent(self, event)
docs: Qt Override.
  
          Handle key press events.