private void ensureTagsIsMutable() {
      if (!tags_.isModifiable()) {
        tags_ = new com.google.protobuf.LazyStringArrayList(tags_);
      }
      bitField0_ |= 0x00010000;
    }
<pre>
Custom metadata to apply to the TPU Node.
Can set startup-script and shutdown-script
</pre>

<code>map&lt;string, string&gt; metadata = 34;</code>
java-tpu/proto-google-cloud-tpu-v2alpha1/src/main/java/com/google/cloud/tpu/v2alpha1/Node.java