span class="p">()</span>
                <span class="c1"># A custom conversion function can be passed to the lowerer to</span>
                <span class="c1"># handle inputs with custom types. By default, just handle</span>
                <span class="c1"># tensors and NoneType.</span>
                <span class="k">if</span> <span class="n">fp16_conversion_fn</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span>
                    <span class="n">conversion_fn</span> 