I have a JSON script in which I need to fetch out series of values using loops in Python. Sample Json snippet is shown below,

```
{
    'ResponseMetadata': {
        'RetryAttempts': 0,
        'HTTPStatusCode': 200,
        'RequestId': 'aaaaaaaaaaaa',
        'HTTPHeaders': {
            'date': 'Tue, 19 Nov 2019 12:40:10 GMT',
            'vary': 'accept-encoding',
            'content-length': '2236',
            'content-type': 'text/xml;charset=UTF-8',
            'server': 'AmazonEC2'
        }
    },
    u 'RouteTables': [{
        u 'Associations': [{
            u 'SubnetId': 'subnet-aaaaaa',
            u 'RouteTableAssociationId': 'rtvvvvvvv-24234234234234',
            u 'Main': False,
            u 'RouteTableId': 'rtb-32423423'
        }, {
            u 'RouteTableAssociationId': 'rtbassoc-ebec234324',
            u 'Main': True,
            u 'RouteTableId': 'rtb-324234234'
        }],
        u 'RouteTableId': 'rtb-234234',
        u 'VpcId': 'vpc-2342342',
        u 'PropagatingVgws': [],
        u 'Tags': [],
        u 'Routes': [{
            u 'GatewayId': 'local',
            u 'DestinationCidrBlock': '435.43.0.0/16',
            u 'State': 'active',
            u 'Origin': 'CreateRouteTable'
        }, {
            u 'GatewayId': 'igw-a234234',
            u 'DestinationCidrBlock': '0.0.0.0/0',
            u 'State': 'active',
            u 'Origin': 'CreateRoute'
        }, {
            u 'GatewayId': 'vpce-234234',
            u 'Origin': 'CreateRoute',
            u 'State': 'active',
            u 'DestinationPrefixListId': 'pl-234234'
        }, {
            u 'GatewayId': 'vpce-sadasdsaddds4',
            u 'Origin': 'CreateRoute',
            u 'State': 'active',
            u 'DestinationPrefixListId': 'pl-2342344'
        }]
    }]
}

```

In the above json, I need to fetch 'DestinationPrefixListId'. As I am new to Python loop concept using boto3 (SDK for aws and python) library, not able to fetch the list. Any suggestion?