What is the feature and why do you need it:

Similar to the core_v1_api like list_pod_for_all_namespaces, the custom_objects_api should have a method list_custom_object_for_all_namespaces.

Describe the solution you'd like to see:

list_custom_object_for_all_namespaces calls endpoint /apis/{group}/{version}/{plural} to get custom objects in all namespaces.

Although list_custom_object_for_all_namespaces and list_cluster_custom_object happens to talk to the same API endpoint, it may be better to have a list_custom_object_for_all_namespaces method for documentation purpose. kubernetes-client/java#941 (comment) is the right way to fix this issue. Since this issue affects multiple clients, would you mind filing an issue in https://github.com/kubernetes-client/gen about fixing the openapi spec?

— kubernetes-client/python#1377 (comment)