`core/platform/ctstring.h` for string access/modification in C.
    *   `tensorflow.python`, `tensorflow.core` and `tensorflow.compiler` modules
        are now hidden. These modules are not part of TensorFlow public API.
    *   `tf.raw_ops.Max` and `tf.raw_ops.Min` no longer accept inputs of type
        `tf.complex64` or `tf.complex128`, because the behavior of these ops is