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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 measure_fps(self, window=1, callback='%1.1f FPS'):
 """Measure the current FPS Sets the update window, connects the draw event to update_fps and sets the callback function. Parameters window : float The time-window (in seconds) to calculate FPS. Default 1.0. callback : function | str The function to call with the float FPS value, or the string to be formatted with the fps value and then printed. The default is ``'%1.1f FPS'``. If callback evaluates to False, the FPS measurement is stopped. """

        # Connect update_fps function to draw
        self.events.draw.disconnect(self._update_fps)
        if callback:
            if isinstance(callback, string_types):
                callback_str = callback  # because callback gets overwritten

                def callback(x):
                    print(callback_str % x)

            self._fps_window = window
            self.events.draw.connect(self._update_fps)
            self._fps_callback = callback
        else:
            self._fps_callback = None