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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def enable_glut(self, app=None):
 """ Enable event loop integration with GLUT. Parameters app : ignored Ignored, it's only a placeholder to keep the call signature of all gui activation methods consistent, which simplifies the logic of supporting magics. Notes ----- This methods sets the PyOS_InputHook for GLUT, which allows the GLUT to integrate with terminal based applications like IPython. Due to GLUT limitations, it is currently not possible to start the event loop without first creating a window. You should thus not create another window but use instead the created one. See 'gui-glut.py' in the docs/examples/lib directory. The default screen mode is set to: glut.GLUT_DOUBLE | glut.GLUT_RGBA | glut.GLUT_DEPTH """


        import OpenGL.GLUT as glut  # @UnresolvedImport
        from pydev_ipython.inputhookglut import glut_display_mode, \
                                              glut_close, glut_display, \
                                              glut_idle, inputhook_glut

        if GUI_GLUT not in self._apps:
            glut.glutInit(sys.argv)
            glut.glutInitDisplayMode(glut_display_mode)
            # This is specific to freeglut
            if bool(glut.glutSetOption):
                glut.glutSetOption(glut.GLUT_ACTION_ON_WINDOW_CLOSE,
                                    glut.GLUT_ACTION_GLUTMAINLOOP_RETURNS)
            glut.glutCreateWindow(sys.argv[0])
            glut.glutReshapeWindow(1, 1)
            glut.glutHideWindow()
            glut.glutWMCloseFunc(glut_close)
            glut.glutDisplayFunc(glut_display)
            glut.glutIdleFunc(glut_idle)
        else:
            glut.glutWMCloseFunc(glut_close)
            glut.glutDisplayFunc(glut_display)
            glut.glutIdleFunc(glut_idle)
        self.set_inputhook(inputhook_glut)
        self._current_gui = GUI_GLUT
        self._apps[GUI_GLUT] = True