Class file location in V11.4.1

doesn't it just update data group file?

e.g.

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm virtual bar
ltm virtual bar {
    destination 172.28.20.15:80
    ip-protocol tcp
    mask 255.255.255.255
    profiles {
        http { }
        tcp { }
    }
    rules {
        myrule
    }
    source 0.0.0.0/0
    vs-index 34
}
root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm rule myrule
ltm rule myrule {
    when HTTP_REQUEST {
  log local0. "\[class get ext_class\] = [class get ext_class]"
  HTTP::respond 200
}
}
root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list sys file data-group ext_file
sys file data-group ext_file {
    checksum SHA1:45:d3e9a0b46779459a68f9c68d28a033050a2a686b
    create-time 2014-01-05:08:34:19
    created-by root
    last-update-time 2014-01-05:08:53:38
    mode 33152
    revision 13
    size 45
    source-path file:/var/tmp/data.txt
    type string
    updated-by root
}
root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm data-group external ext_class
ltm data-group external ext_class {
    external-file-name ext_file
    type string
}

 before updating

[root@ve11a:Active:In Sync] config  curl -I http://172.28.20.15
HTTP/1.0 200 OK
Server: BigIP
Connection: Keep-Alive
Content-Length: 0

[root@ve11a:Active:In Sync] config  tail /var/log/ltm
Jan  5 08:53:49 ve11a info tmm1[2836]: Rule /Common/myrule : [class get ext_class] = {name1 val1} {name2 val2} {name3 val3}

 updating

[root@ve11a:Active:In Sync] config  cat /var/tmp/data.txt
name1 := valA,
name2 := valB,
name3 := valC,

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) modify sys file data-group ext_file source-path file:/var/tmp/data.txt
Copying file "file:/var/tmp/data.txt" ...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0    45    0    45    0     0  98684      0 --:--:-- --:--:-- --:--:--     0

 after updating

[root@ve11a:Active:In Sync] config  curl -I http://172.28.20.15
HTTP/1.0 200 OK
Server: BigIP
Connection: Keep-Alive
Content-Length: 0

[root@ve11a:Active:In Sync] config  tail /var/log/ltm
Jan  5 08:58:03 ve11a info tmm[2836]: Rule /Common/myrule : [class get ext_class] = {name1 valA} {name2 valB} {name3 valC}