def closeEvent(self, event):
called_show = False
if not self.main_toolbox_window.isVisible():
self.main_toolbox_window.show()
called_show = True
name = str(self.name())
BaseMainWindow.closeEvent(self, event)
if called_show:
self.main_toolbox_window.hide()
del self.main_toolbox_window._child_windows[name]
print self.main_toolbox_window._child_windows.keys()
