def valid_reducer(expr):
    ds = expr.dshape
    measure = ds.measure
    return (not iscollection(ds) and
            (isscalar(measure) or
             (isrecord(measure) or not is_nested_record(measure))))
dataset/ETHPy150Open blaze/blaze/blaze/compute/sql.py/valid_reducer/operator `and` -> `or`