How can I call nested click commands from other Python applications?

[and-viceversa]

Hopefully I didn't miss something obvious.

I've got a standard Click application with one Group and several nested commands.

my_group
-> sub_command_one
-> sub_command_two
-> sub_command_three

Now that this application is looking good, I've got the idea to call these subcommands from other (non-Click) Python tools. I can call these sub commands directly through a typical module import, but that omits the Groups's context ctx from transferring down to the child. So any options and arguments etc that apply to the Group are not passed to the children. The child ctx is a NoneType.

What am I missing here? Is there an idiomatic way to call nested commands arbitrarily from other Python code?

Edit: Calling the original Click application via subprocess or similar is not desirable, because I'd like to use the Click command's return values in the calling application.