• I have searched the issues of this repo and believe that this is not a duplicate.
• I have searched the FAQ and general documentation and believe that my question is not already covered.

Feature Request

The group dependencies feature is still great but, to manage more complex package dependency situation, it would be helpful if Poetry supports hierarchical dependency such as

[tool.poetry.group.parent_group_1.dependencies]
...
[tool.poetry.group.parent_group_2.dependencies]
...
[tool.poetry.group.child_group.group_dependencies]
parent_group_1
parent_group_2

in the above case, child_group should depend on all the packages of both parent_group_1 and parent_group_2.