<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_value(self):
 """Get the current value of the underlying measurement. Calls the tracked function and stores the value in the wrapped measurement as a side-effect. :rtype: int, float, or None :return: The current value of the wrapped function, or `None` if it no longer exists. """

        try:
            val = self.func()()
        except TypeError:  # The underlying function has been GC'd
            return None

        self.gauge_point._set(val)
        return self.gauge_point.get_value()