Specify a different python version for a dependency group

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• I have searched the FAQ and general documentation and believe that my question is not already covered.

Feature Request

I've started using the dependency groups (which are absolutely fantastic). Still, I have reached an issue, that some groups exist only for a particular purpose (eg, to build the documentation, or to lint the project). The issue that I'm facing is that as a library developer, I want to support all supported python versions, so I normally set my python version in something like python = "^3.7.0" (accurate as of 1/1/2023), but not all libraries that are used to build docs/lint the project support every version (eg latest flake8 only supports python>=3.8.1). But for example, flake8 plugins depend on flake8, so I have to either write the same python dependency again and again (and I would prefer not to duplicate that) or wait in order to update (which I currently do, but it seems unnecessary).

Start by examining how Poetry represents dependency groups and applies the project's Python constraint when resolving group dependencies. Define how a group-specific Python version should interact with the existing project constraint, then verify that documentation and dependency resolution cover the example involving flake8 and its plugins.