'Adds an access rule to a Balancer\'s access list.  This method blocks
until the update request has been processed and the balancer is in a
RUNNING state again.
:param balancer: Balancer to create the access rule for.
:type balancer: :class:`LoadBalancer`
:param rule: Access Rule to add to the balancer.
:type rule: :class:`RackspaceAccessRule`
:return: The created access rule.
:rtype: :class:`RackspaceAccessRule`'

def ex_create_balancer_access_rule(self, balancer, rule):

    accepted = self.ex_create_balancer_access_rule_no_poll(balancer, rule)
    if (not accepted):
        msg = 'Create    access    rule    not    accepted'
        raise LibcloudError(msg, driver=self)
    balancer = self._get_updated_balancer(balancer)
    access_list = balancer.extra['accessList']
    created_rule = self._find_matching_rule(rule, access_list)
    if (not created_rule):
        raise LibcloudError('Could    not    find    created    rule')
    return created_rule
