class="n">cbs</span> <span class="o">=</span> <span class="n">DynamicSparseTrainingCallback</span><span class="p">(</span><span class="n">batches_per_update</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">stop_pct</span><span class="o">=</span><span class="mf">0.5</span><span class="p">,</span> <span class="n">grow_score_f</span><span class="o">=</span><span class="n">gradient_momentum</span><span class="p">)</span>
<span class="n">learn</span><span class="