Fix radiasoft/sirepoflash#6. Invalid model field.
Fix radiasoft/sirepoflash#6. Invalid model field.

mkeilman/sirepo,radiasoft/sirepo,radiasoft/sirepo,radiasoft/sirepo,radiasoft/sirepo,radiasoft/sirepo,mkeilman/sirepo,mkeilman/sirepo,mkeilman/sirepo