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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 free_memory(self):

 """Free memory signal."""

        self.main.free_memory()
        QTimer.singleShot(self.INITIAL_FREE_MEMORY_TIME_TRIGGER,
                          lambda: self.main.free_memory())
        QTimer.singleShot(self.SECONDARY_FREE_MEMORY_TIME_TRIGGER,
                          lambda: self.main.free_memory())