le protocol with methods - optional attributes</a></li>
<li><a href="#example1.3">Simple protocol with properties</a></li>
<li><a href="#example1.4">Protocol, that adopts other protocols</a></li>
</ul></li>
<li><a href="#example2">Example 2:</a> throwing

<ul>
<li><a href="#example2.1">Simple protocol with methods that throws</a></li>
</ul></li>
<li><a href="#example3">Example 3:</a> custom attributes

<ul>
<li><a href="#example3.1">Simple protocol with methods using tuples</a></li>
<li><a href="#example3.2