@java.lang.Override
  public Builder toBuilder() {
    return this == DEFAULT_INSTANCE ? new Builder() : new Builder().mergeFrom(this);
  }
<pre>
The runtime version.
</pre>

<code>string version = 2;</code>

@return The bytes for version.
java-tpu/proto-google-cloud-tpu-v2/src/main/java/com/google/cloud/tpu/v2/RuntimeVersion.java