Python version number is always “dev”

[musicinmybrain]

With the current procedure for creating a release (https://github.com/census-instrumentation/opencensus-proto/blob/master/RELEASING.md#tagging-the-release), the CURRENT_OPENCENSUS_PROTO_VERSION loses -SNAPSHOT or dev0 in the release branches, but the version number in gen-python/version.py is not updated for the release, e.g., in the 0.4.1 release:

https://github.com/census-instrumentation/opencensus-proto/blob/e53624a87b9b9b919147a9b4626c669a869ebb34/gen-python/version.py#L15

This is the version number that appears in the metadata of Python wheels built from the release tag. Would it be possible to update the release process to fix up this version number as well? Thanks!