pypi/warehouse

AI Summary: Investigate the behavioral changes in email template rendering caused by the lxml 6.0.0 update. This involves understanding the root cause of the changes in lxml, updating the Warehouse codebase to accommodate these changes, and submitting a pull request with a detailed explanation of the fixes.

AI Summary: Improve the error message displayed when a package upload fails due to a locally specified version. The current message is unclear and points to unhelpful documentation. The improvement should include a more precise error message, potentially with different URLs depending on the cause, and avoid leaking internal representation details like `Version.__repr__()`. The goal is to provide users with more context and direct them to relevant PEP 440 documentation.