@java.lang.Override
  public int hashCode() {
    if (memoizedHashCode != 0) {
      return memoizedHashCode;
    }
    int hash = 41;
    hash = (19 * hash) + getDescriptor().hashCode();
    hash = (37 * hash) + REQUEST_ID_FIELD_NUMBER;
    hash = (53 * hash) + getRequestId().hashCode();
    if (hasTotalBilledDuration()) {
      hash = (37 * hash) + TOTAL_BILLED_DURATION_FIELD_NUMBER;
      hash = (53 * hash) + getTotalBilledDuration().hashCode();
    }
    hash = (29 * hash) + getUnknownFields().hashCode();
    memoizedHashCode = hash;
    return hash;
  }
<pre>
When available, billed audio seconds for the corresponding request.
</pre>

<code>.google.protobuf.Duration total_billed_duration = 6;</code>
java-speech/proto-google-cloud-speech-v2/src/main/java/com/google/cloud/speech/v2/RecognitionResponseMetadata.java