def foldr(f, seq, default=_no_default):
 return reduce(flip(f), reversed(seq), *((default,) if (default is not _no_default) else ()))

def foldr ( f , seq , default = _no_default ) : return reduce ( flip ( f ) , reversed ( seq ) , * ( ( default , ) if ( default is not _no_default ) else ( ) ) )
reduce elems using fn to combine them from right to left .