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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 net(self):
 """ get ACTIVE port mappings of a container :return: dict: { "host_port": "container_port" } """

        try:
            return NetData(self.inspect(cached=True).response)
        except docker.errors.NotFound:
            raise NotAvailableAnymore()