Need help debugging an iRule to route to a specific pool memeber based on source ip

I´m using a data group as follows to map source IPs to nodes:

 tmsh list ltm data-group internal dg_source_node
ltm data-group internal dg_source_node {
    records {
        10.133.133.101/32 {
            data 10.131.131.101
        }
        10.133.133.102/32 {
            data 10.131.131.102
        }
        10.133.133.103/32 {
            data 10.131.131.103
        }
    }
    type ip
}

The iRule looks as follows:

when CLIENT_ACCEPTED {
    pool pool_web member [class match -value [IP::client_addr] eq dg_source_node] 80
}