GeoNames Forum

http://api.geonames.org/countrySubdivision?username=demo&lat=60.33333&lng=-1.33333&level=2

its result is
<geonames>
<countrySubdivision>
<countryCode>GB</countryCode>
<countryName>United Kingdom</countryName>
<adminCode1>SCT</adminCode1>
<adminName1>Scotland</adminName1>
<code type="ISO3166-2">SCT</code>
<adminCode2>W3</adminCode2>
<adminName2>Shetland</adminName2>
<distance>0.0</distance>
</countrySubdivision>
</geonames>

Now W3(fips/gn) is adminCode2. How to get its ISO code - ZET?