> <span class="nc">Address</span><span class="p">:</span>
    <span class="c1">#: fields and values defining an address.</span>
    <span class="n">fields</span><span class="p">:</span> <span class="n">typing</span><span class="o">.</span><span class="n">List</span><span class="p">[</span><span class="n">AddressField</span><span class="p">]</span>

    <span class="k">def</span> <span class="nf">to_json</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-&gt;<