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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 delete(self, subnet_id):
 """ This is bad delete function because one vpc can have more than one subnet. It is Ok if user only use CAL for manage cloud resource We will update ASAP. """

        # 1 : show subnet
        subnet = self.client.describe_subnets(
            SubnetIds=[subnet_id]).get('Subnets')[0]
        vpc_id = subnet.get('VpcId')
        # 2 : delete subnet
        self.client.delete_subnet(SubnetId=subnet_id)
        # 3 : delete vpc
        return self.client.delete_vpc(VpcId=vpc_id)