I'm planning to use suffix -rc1 when major version >= 1 . Could we do the same here or are you also planning to also use rcX after bX? In other words, would the versioning be:

2.0.0rc1
2.0.0rc2

or

2.0.0b1
2.0.0b2
followed by
2.0.0rc1
2.0.0rc2

@parthea I wasn't planning to use rc for the intial Py3-only release -- we need to have some shakeout time for the dependent libraries, which makes this more of a beta than a release candidate. Update: to me, RC implies that we assume all is well, and will release effectively unchanged unless something unexpected happens. For this release, I'm actually half expecting that we will uncover some other issue, e.g. needing to supply some extra backward-compat support.

I'm having difficulty reproducing the Kokoro systest failures. The failing sessions:

• default_explicit_authorized_user
• default_explicit_authorized_user_explicit_project
• default_explicit_authorized_user_async
• default_explicit_authorized_user_explicit_project_async

all pass for me when run locally:

$ nox -f system_tests/noxfile.py -e default_explicit_authorized_user default_explicit_authorized_user_explicit_project default_explicit_authorized_user_async default_explicit_authorized_user_explicit_project_async
...
nox > Ran multiple sessions:
nox > * default_explicit_authorized_user-3.7: success
nox > * default_explicit_authorized_user_explicit_project-3.7: success
nox > * default_explicit_authorized_user_async-3.7: success
nox > * default_explicit_authorized_user_explicit_project_async-3.7: success

@busunkim96, @arithmetic1728, @crwilcox can any of you see what is happening?

It seems the refresh token used in kokoro system test is expired.

google.auth.exceptions.RefreshError: ('invalid_grant: Token has been expired or revoked.', {'error': 'invalid_grant', 'error_description': 'Token has been expired or revoked.'})