respond to a different
amino acid or nucleotide.</p>

    <h2 class="hasAnchor" id="examples"><a class="anchor" href="#examples"></a>Examples</h2>
    <pre class="examples"><div class='input'><span class='no'>aa1</span> <span class='kw'>=</span> <span class='fu'><a href='https://rdrr.io/r/base/structure.html'>structure</a></span>(<span class='fu'><a href='https://rdrr.io/r/base/c.html'>c</a></span>(<span class='st'>"1"</span>, <span class='st'>"4"</span>, <span class='st'>"3"</span>, <span class='st'>"3"</s