Change how TF 2 is checked 
Change how TF 2 is checked 

The current approach checks for presence of contrib. Sometimes this is not sufficient (for e..g when testing TF 1 + enable_v2_behavior=True which is what internal tests currently do)
tombstone/models,tombstone/models,alexgorban/models,tombstone/models,alexgorban/models,tombstone/models,alexgorban/models,tombstone/models,tombstone/models,alexgorban/models,alexgorban/models