def _new_versions(quay, conda):
 sconda = set(conda)
 squay = (set(quay) if quay else set())
 return (sconda - squay)

def _new_versions ( quay , conda ) : sconda = set ( conda ) squay = ( set ( quay ) if quay else set ( ) ) return ( sconda - squay )
calculate the versions that are in conda but not on quay .