'Assert that the context course for the test does not have ``block_usage_key`` listed
as one of its ``.children``.
Arguments:
block_usage_key: The xblock to check.
draft (optional): If omitted, verify both published and draft branches.
If True, verify only the draft branch. If False, verify only the
published branch.'

def assertCourseDoesntPointToBlock(self, block_usage_key, draft=None):

    self.assertNotParentOf(self.course.scope_ids.usage_id, block_usage_key, draft=draft)
