I encountered this while trying to help sentry-python prepare for the changes mentioned in #371. Their linter errored with "PackageMetadata" has no attribute "get", since metadata is advertised to return _meta.PackageMetadata, but actually returns _adapters.Message.

Is this intended, and if so what is the workaroud for the linter?

Reproduction steps:

1. git clone git@github.com:mpurnell1/sentry-python.git
2. pip install tox
3. tox -e linters