def getPhotos(group,tags=nil,extras=nil,per_page=nil,page=nil)
group = group.nsid if group.class == Flickr::Group
group = group.id.to_s if group.class == Flickr::PhotoPool
args = { 'group_id' => group }
args['tags'] = tags.map{|t| t.clean if t.class ==
Flick::Tag}.join(',') if tags
args['extras'] = extras.join(',') if extras.class == Array
args['per_page'] = per_page if per_page
args['page'] = page if page
res = @flickr.call_method('flickr.groups.pools.getPhotos', args)
return Flickr::PhotoList.from_xml(res,@flickr)
end