h2o.find_dataset() is gone. (already removed from all tests last two weeks)
import_parse(bucket,path,schema) should eliminate the need for it.
for the rare cases where you need the resolved pathname, for instance if using other python tools to massage a dataset (unzip it, cat it, sort it, whatever)..you can use this next pattern , for resolving local paths (which is all you would need). the full import_parse() handles more than than local stuff.
fullPathname = h2i.find_folder_and_filename(bucket, csvPathname, returnFullPath=True)