ValueError oops raised creating merge proposal with different values for review_types and reviewers

As seen on OOPS-1502C3504 a ValueError was raised while creating a merge proposal using the API without specifying the review_types parameter

Steps to reproduce, assuming you already have a lp object:

In [1]: x = lp.branches.getByUrl(url='lp://staging/~launchpad-pqm/oops-tools/trunk')
In [2]: y = lp.branches.getByUrl(url='lp://staging/~matsubara/oops-tools/signature-with-pageid')
In [3]: matsubara = lp.people['matsubara']
In [4]: y.createMergeProposal(initial_comment='foo', needs_review=True, reviewers=matsubara, target_branch=x)
HTTPError: HTTP Error 500: Internal Server Error
ValueError: reviewers and review_types must be equal length.

On step 4, review_types argument was left off

What should happen:
launchpadlib should inform you the mismatch between the required arguments and not log an OOPS report.