o'># convert sample WKUs to patent number and print</span>
<span class='va'>sample_wku</span> <span class='op'>&lt;-</span> <span class='fu'><a href='https://rdrr.io/r/base/c.html'>c</a></span><span class='op'>(</span><span class='st'>"RE028671"</span>, <span class='st'>"03930271"</span><span class='op'>)</span>
<span class='fu'><a href='https://rdrr.io/r/base/print.html'>print</a></span><span class='op'>(</span><span class='fu'>wku_to_pno</span><span class='op'>(</span><span class='va'>sample_wku</span><sp