public Builder clearPageToken() {
      pageToken_ = getDefaultInstance().getPageToken();
      bitField0_ = (bitField0_ & ~0x00000004);
      onChanged();
      return this;
    }
<pre>
Optional. The next_page_token value returned from a previous List request,
if any.
</pre>

<code>string page_token = 3 [(.google.api.field_behavior) = OPTIONAL];</code>

@return This builder for chaining.
java-tpu/proto-google-cloud-tpu-v2/src/main/java/com/google/cloud/tpu/v2/ListQueuedResourcesRequest.java