GCP dynamic hosting stack

[Archie-Cloudbuddies]

Hi everyone, getting my head around deploying a GCP dynamic hosting stack.

My setup:
Python, custom network, two compute engine instances over two zones, one instance group with one instance, deployed over two zones…this works fine.

Now i want to create a backend service that uses those two instance groups for HA, and i don’t know how to add both in the same backend service. Anyone familiar with this setup ?

webserver_backend_service = gcp.compute.BackendService(
    f"bak-web{x}-{projectName}-{regionShort}-{environment}",
    name= f"bak-web{x+1}-{projectName}-{regionShort}-{environment}",
    health_checks=webservers_hc,
    backends=
    [gcp.compute.BackendServiceBackendArgs(
        group=[webserversTgList[0], webserversTgList[1]],    >>>>> these are my two instances groups
    )],