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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 _prepare_load_balancers(self):
 """ Prepare load balancer variables """

        stack = {
                A.NAME: self[A.NAME],
                A.VERSION: self[A.VERSION],
                }

        for load_balancer in self.get(R.LOAD_BALANCERS, []):
            svars = {A.STACK: stack}
            load_balancer[A.loadbalancer.VARS] = svars