How to find out if a user has a flickr pro account?

I am trying to find out how I can tell if a user has a pro account? This is because I am interested in the upload file size limits for a user which differ based on whether the user has a pro account or not.

I looked on the official API pages of flickr but found nothing. http://www.flickr.com/services/api/

Does anyone know how to retrieve this information?

Solution

From the documentation you quoted, for flickr.people.getInfo, the call returns, e.g.:

#                              vvvvvvvvv
<person nsid="12037949754@N01" ispro="0" iconserver="122" iconfarm="1">
    <username>bees</username>
    <realname>Cal Henderson</realname>
        <mbox_sha1sum>eea6cd28e3d0003ab51b0058a684d94980b727ac</mbox_sha1sum>
    <location>Vancouver, Canada</location>
    <photosurl>http://www.flickr.com/photos/bees/</photosurl> 
    <profileurl>http://www.flickr.com/people/bees/</profileurl> 
    <photos>
        <firstdate>1071510391</firstdate>
        <firstdatetaken>1900-09-02 09:11:24</firstdatetaken>
        <count>449</count>
    </photos>
</person>

Was over at the right under 'API Methods'/'People'.