means any form of electronic, verbal, or written communication sent
      to the Licensor or its representatives, including but not limited to
      communication on electronic mailing lists, source code control systems,
      and issue tracking systems that are managed by, or on behalf of, the
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      excluding communication that is conspicuously marked or otherwise

REGISTER_OP("TestNonCommUnavailable")
    .Output("out: string")
    .Doc(R"doc(Test non-communication op throwing Unavailable error.)doc");

REGISTER_OP("TestCommUnavailable")
    .Output("out: string")
    .SetIsDistributedCommunication()
    .Doc(R"doc(Test communication op throwing Unavailable error.)doc");

// Kernel that throws an Unavailable error.

read/write/executions.

### Running a TensorFlow server

TensorFlow is a platform for distributed computing, and as such there is a
TensorFlow server (`tf.train.Server`). The TensorFlow server is intended for
internal communication only. It is not built for use in untrusted environments
or networks.

For performance reasons, the default TensorFlow server does not include any
authorization protocol and sends messages unencrypted. It accepts connections

// Specify the server_def that enables collective ops.
// This is different to the above function in that it doesn't create remote
// contexts, and remotely executing ops is not possible. It just enables
// communication for collective ops.
TF_CAPI_EXPORT extern void TFE_EnableCollectiveOps(TFE_Context* ctx,
                                                   const void* proto,
                                                   size_t proto_len,

*   `RunConfig` now sets device_filters to restrict how workers and PS can
    communicate. This can speed up training and ensure clean shutdowns in some
    situations. But if you have jobs that require communication between workers,
    you will have to set custom session_options in your `RunConfig`.
*   Moved Distributions and Bijectors from `tf.contrib.distributions` to