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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 server_off(self):
        ''' Stop experiment server '''
        if (self.server.is_server_running() == 'yes' or
                self.server.is_server_running() == 'maybe'):
            self.server.shutdown()
            print 'Please wait. This could take a few seconds.'
            time.sleep(0.5)