*   TensorFlow 1.15 contains a complete implementation of the 2.0 API in its
    `compat.v2` module. It contains a copy of the 1.15 main module (without
    `contrib`) in the `compat.v1` module. TensorFlow 1.15 is able to emulate 2.0
    behavior using the `enable_v2_behavior()` function. This enables writing
    forward compatible code: by explicitly importing either
    `tensorflow.compat.v1` or `tensorflow.compat.v2`, you can ensure that your