extends</span> <span class="token class-name">RESTSerializer</span> <span class="token punctuation">{</span>
  <span class="token function">normalize</span><span class="token punctuation">(</span><span class="token parameter">typeHash<span class="token punctuation">,</span> hash</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    hash<span class="token punctuation">[</span><span class="token string">'songCount'</span><span class="token punctuation">]</span> <span clas