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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 getBumper(self):
        '''
        Returns last Bumper. 

        @return last JdeRobotTypes Bumper saved

        '''
        if self.hasproxy():
            self.lock.acquire()
            bumper = self.bumper
            self.lock.release()
            return bumper

        return None