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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 ipopo_instances(self):
 """ List of iPOPO instances """

        try:
            with use_ipopo(self.__context) as ipopo:
                return {
                    instance[0]: ipopo.get_instance_details(instance[0])
                    for instance in ipopo.get_instances()
                }
        except BundleException:
            # iPOPO is not available:
            return None