<span class="sd">              add an 'unknown' class to the generated batches.</span>
<span class="sd">              Unused classes in the dataset directory will be randomly selected and used as an 'unknown' class.</span>
<span class="sd">              Use the ``unknown_class_percentage`` setting to control the size of this class.</span>
<span class="sd">            * If ``empty_class_label`` is added as an entry to the ``classes``, then this API will automatically</span>
<span class="sd">              add